Pete Hegseth reportedly signed a memo last month permitting the Department of Homeland Security (DHS) to test a non-lethal “heat ray” for potential use at the US southern border.

The “heat ray”, known as the Active Denial System, is a military-grade weapon that shoots an energy beam causing “a sensation of intense heat on the surface of the skin”, according to a 2009 National Defense University case study on the weapon.

The sensation “creates an intolerable sensation and reflexive movement” such as ducking or running.

In a memo, first obtained by CNN, the US defense secretary authorized a “temporary loan” of the Active Denial System to the DHS for seven months beginning in September. The DHS can request further use of the Pentagon system if needed.

A spokesperson for Customs and Border Protection (CBP) said in a statement it was “continually evaluating new technology, especially technology that can save lives while simultaneously enhancing national security effectiveness”.

It is unclear what the DHS plans to use the Active Denial System for exactly, but the memo permits the department to use it for potential operations at the US-Mexico border.

When used, the Active Denial System can produce an invisible beam of 95 gigahertz that penetrates about 1/64th of an inch into the skin, causing a burning sensation. (The system is technically not a “heat ray” because it uses millimeter waves, not infrared, Forbes reported in 2020.)

Pentagon officials have compared the feeling to a blast of heat when opening a hot oven, according to CNN. The feeling is temporary, lasting between 10 and 15 minutes.

Here’s the full story:

Related: Pete Hegseth reportedly authorizes DHS to test ‘heat ray’ at US-Mexico border

Reporting from Miami

Donald Trump has been ordered by a US judge to cooperate with the discovery process mandated for his lawsuit against the BBC and to sit for a deposition by 11 December – or else he could be subject to sanctions, including the possible dismissal of the $10bn lawsuit.

The lawsuit stems from a Panorama documentary aired by the BBC that spliced together comments made by Trump during a rally on 6 January 2021, before the US Capitol riot. While the broadcast was not readily available to view in Florida, Trump’s team has argued that he was personally damaged by the broadcast under Florida’s Unfair and Deceptive Trade Practices Act.

During a lengthy hearing dealing with a variety of discovery issues, federal magistrate judge Enjoliqué Lett on Thursday also rejected a request by Trump’s legal team to prevent the seven-hour-long deposition from being videotaped, though it will only be accessible to attorneys in the case.

Lett agreed with contentions from the BBC’s lawyers that Trump’s team had not been sufficiently forthcoming in handing over internal documents relevant to the case ahead of an 18 December deadline for discovery.

“We still have a completely lopsided [situation] here on discovery. They have produced absolutely nothing of any substance,” attorney Charles Tobin, on behalf of the BBC, argued in a Miami courtroom. The documents that Trump’s team have turned over have primarily been either pulled from the internet or provided by the BBC itself.

“It strains credulity that a thorough search has been done in order to determine that all of these requests have been responded to,” Lett told Alejandro Brito, Trump’s Florida-based attorney. “The court is not satisfied that anyone is doing a thorough job.”

Related: US judge orders Trump to sit for deposition in $10bn lawsuit against BBC

Before traveling to Nebraska, JD Vance fielded questions from reporters and expressed confidence in possible negotiations between Russia and Ukraine, following Steve Witkoff’s meetings with leadership of both countries in recent days.

“The reason why we haven’t struck a peace deal is because they’ve just been too apart on some of the details of that negotiation,” Vance said. “So, I think Steve re-engaged the process … He feels optimistic. I mean, the nature of these things is you take a swing at it, you see how much progress you can make, and then you go back at it, and sometimes it works, and sometimes it doesn’t.”

While Witkoff said that trilateral talks between Washington, Moscow and Kyiv “at the technical level” would follow his discussions this week, Russia still carried out a massive “demonstrative” attack on Ukraine overnight, bombarding Kyiv with ballistic missiles just hours after Putin’s meeting with Witkoff wrapped up.

The latest strikes killed at least two people and wounded 22, including four children.

Updated

Democrats have 37-point lead over Republicans among likely young voters, new poll finds

Democrats lead Republicans 63% to 26% among likely voters aged 18-29, according to a new poll by Harvard’s Institute of Politics.

However, 33% of young Americans say they will definitely vote in the upcoming midterms, down from 40% who said the same ahead of both the 2018 and 2022 cycles.

In 2024, 56% of men between the ages of 18 and 29 voted for Trump while just 40% of their female peers did so. Harvard’s new poll shows that while women still favor Democrats, 66% to 21%, that number is also robust among young men: 58% to 32%.

Another key takeaway from the survey, the last before the November midterms: only 9% of 18- to 29-year-olds say the nation is generally headed in the right direction, while 62% say it is off on the wrong track and 26% say they are unsure.

Updated

Key election forecaster shifts Ohio gubernatorial race in Dems favor after GOP campaign ad controversy

Following the recent controversy around Vivek Ramaswamy’s campaign ad that features Amy Acton’s estranged mother, Sabato’s Crystal Ball at the Center for Politics – a key election forecaster – has shifted the Ohio gubernatorial race from “toss up” to “leans Democratic”.

As I noted earlier, a number of Republicans, including the outgoing governor Mike DeWine, have criticized the ad, which includes Acton’s mother – who she hasn’t seen since she was removed from her care at age 12 – calling her daughter a “liar”.

Updated

'Deeply troubling': Republican governor of Ohio calls on Ramaswamy to take down campaign ad featuring Democratic opponent's estranged mother

Mike DeWine, the outgoing Republican governor of Ohio, has called on Vivek Ramaswamy’s campaign to take down the recent ad that includes the estranged mother of his Democratic opponent, Amy Acton.

DeWine called the campaign spot “deeply, deeply troubling” and said it was “wrong” to have run it. The governor told reporters today that he would not rescind his endorsement of Ramaswamy in the bitter gubernatorial race against Acton – who served as the health director in DeWine’s administration and guided the state through its Covid-19 pandemic response.

On Wednesday, Acton responded to the recent controversy and told a group of voters said Ramaswamy shouldn’t have “exploited” her mother.

A reminder that Acton and her brother were removed from their mother’s care when Acton was 12, after their stepfather was arrested and charged for raping her. However Arthur remained married to her husband, and they fled the state.

Meanwhile, at an event stumping for Ramaswamy in Cincinnati on Wednesday, JD Vance chided Republicans for their outrage over the ad. The vice-president said he wasn’t going to weigh in on whether the spot was “appropriate or not”. Instead his “message” for fellow elected Republicans was to “stop whining about an advertisement and go win the race in 13 days”.

Updated

Reporting from Anchorage, Alaska

Mary Peltola’s campaign to represent Alaska in the US Senate has taken her to parts of the massive state’s interior that are inaccessible by road and on the frontlines of the cost-of-living crisis she hopes will make her the first Democrat to win the seat in nearly two decades.

She has been to towns where paper towels retail for $40, half a gallon of oat milk goes for $21 and the cost of a new freezer can be quadruple what it is in the state’s largest city, Anchorage, simply because it’s so complicated to get there. Along the Arctic Ocean, she’s heard of communities where power bills have climbed to $1,500 a month because they rely on generators for power and the Iran war has pushed the cost of diesel to new heights.

“Nobody can afford that,” Peltola said in an interview.

Alaska, a right-leaning state that is about twice the size of Texas but the third-least populous in the country, has always been among the more expensive places to live, and the price increases in the state’s rural areas haven’t necessarily been felt to the same degree in the more populous cities and towns.

Yet the state’s Democrats believe circumstances have aligned for them to win a slew of competitive elections in the 3 November midterms. The Senate seat currently held by two-term Republican Dan Sullivan is a top prize.

“In 23 short days, we’re going to be voting both [Republican congressman] Nick Begich and Dan Sullivan out of office, and they richly deserve it,” the chair of the state Democratic party, Eric Croft, said at a press conference last week.

“They are self-serving, self-dealing DC politicians who repeatedly voted to make life harder and more expensive for Alaskans.”

All signs indicate that Republicans are taking seriously the threat posed by Peltola, an Alaska native and former US House lawmaker who supports oil and gas and gun rights. Outside groups have poured in tens of millions of dollars into supporting both candidates, and last week Donald Trump made the long journey from Washington DC to the conservative Matanuska-Susitna valley to rally voters behind Sullivan, who has trailed in some recent polls.

Read the full dispatch here:

Related: Trump’s war and tariffs have battered Alaska. A pro-oil Democrat could flip the key Senate seat

Updated

Today, we’ll also bring you the latest from other states where nominees are getting some help from big names in the final weeks of campaigning.

In Maine, Troy Jackson, the Democratic nominee for US Senate, will get support from progressive firebrand Alexandria Ocasio-Cortzez, the congresswoman from New York. The two will hold a rally in Portland as Jackson attempts to oust Susan Collins, the moderate Republican, from the Senate seat she’s held on to for almost 30 years.

Meanwhile, in Nebraska, Vice-President JD Vance will stump for Pete Ricketts, the GOP senator who is facing a re-election battle against the independent contender Dan Osborn. A reminder that the Democratic nominee, Cindy Burbank, withdrew after the primary earlier this year, in an attempt to shore up more support for Osborn.

Updated

Meanwhile, my colleagues Sam Levine and George Chidi, who have spent years covering voting rights, joined the Guardian’s Stateside with Kai and Carter for an episode all about the Trump administration’s persistent efforts to interfere with the midterm elections – including the justice department charging 28 green card holders in California over alleged voter fraud earlier this week.

As the president attempts to crackdown on non-citizen voting, which experts insist is an extremely rare phenomenon, Sam and George explain how this is part of a wider tactic push to throw the results of the midterms into doubt.

Updated

Guardian reporters answer your questions about Trump's mass deportation agenda and the midterms

Also today, my colleagues Maanvi Singh, José Olivares and Sam Levin will take your questions about how Trump’s mass deportation agenda will shape the upcoming midterm elections.

During the second Trump administration, ICE arrests have reached record levels, operations have become deadly, and immigration raids have hit politicians’ homes. Our reporting has documented the experiences of those directly affected by the harsh conditions in detention centers and resistance to ICE agents on the ground.

Send your questions or join them at 12pm ET to see how this will play out for voters in fewer than two weeks.

Related: How will Trump’s mass deportation agenda shape the US midterm elections? Our reporters answer your questions

We’re also tracking the fallout over a controversial ad from Vivek Ramaswamy – the Republican gubernatorial nominee in Ohio – which featured the estranged mother of his Democratic opponent, Amy Acton.

In the campaign spot her mother, Donna Arthur, was critical of Acton and called her a “liar”.

On Wednesday, Acton responded to the controversy and told a group of voters said Ramaswamy shouldn’t have “exploited” her mother.

A reminder that Acton and her brother were removed from their mother’s care when Acton was 12, after their stepfather was arrested and charged for raping her. However Arthur remained married to her husband, and they fled the state.

Acton went on to describe the recent advert as “another sign of this time, where enough is enough … do anything, say anything just to get ahead. And I think Ohioans are smarter than that.”

Donald Trump will begin his day in Washington before traveling to Sioux City, Iowa, for another campaign rally, as part of his week-long midterm blitz.

He’ll stump for Ashley Hinson, the Republican congresswoman and nominee for the state’s open US Senate, who is trailing in the polls against her opponent, the Democratic state legislator Josh Turek.

The president will also campaign on behalf of Zach Lahn, a businessman and the GOP nominee for governor, who is facing a tough competition against the Democratic state auditor Rob Sand in November.

Iowa has become an unexpected battleground this midterm cycle, with voters particularly frustrated about the impact on the war in Iran – namely the high cost of fuel and fertiliser. Democrats are hoping for an upset in a state where they haven’t won a US Senate set since 2008.

Trump will take the stage at 7pm ET, and we’ll bring you the latest lines.

Updated

Texas Senate race neck-and-neck as midterms loom

New polls shows the super-tight race in Texas where Democratic candidate James Talarico is challenging Republican Ken Paxton in the US Senate race. Earlier this week, Talarico also won the endorsement of George W Bush’s brother.

New polling from Emerson College shows Talarico at 48%, just in front of Paxton at 46% – with about 5% undecided.

Neil Bush, a son of former president George HW Bush and a lifelong Republican, announced on Tuesday that he crossed party lines to vote for Talarico.

In a Facebook post, Neil Bush said he chose to vote early for Talarico over Ken Paxton, the current Texas attorney general, because he was “deeply troubled” by Paxton’s conduct and was “enormously impressed” by Talarico’s principles.

As a moderate Republican, Neil Bush’s statement on the competitive Senate race in Texas reflects views from a faction of the party that often disagrees with Donald Trump while holding traditional conservative views.

I have been deeply troubled by Paxton’s conduct as Texas attorney general, particularly his decision to challenge the results of the 2020 presidential election in other states in an effort to help Donald Trump remain in power.

The former president’s son and brother of George W Bush expressed concern about Paxton’s past controversies, including Paxton’s 2023 Texas state legislature impeachment and acquittal, as well as Paxton’s loyalty to Trump.

I have been a Republican for most of my life, and I still believe deeply in many traditional Republican principles. But character matters more than party affiliation. Our democracy depends on leaders who respect our institutions, tell the truth, accept accountability, and seek to unite rather than divide.

Updated

Trump praised supporters for punching protesters at rally

Multiple protesters were removed from Donald Trump’s rally at South Carolina’s Clemson University on Wednesday, including one who was apparently punched by a rally attender – to the US president’s delight.

“That was great, man. Wow. Man, I loved that. I watched that,” Trump said. “That was incredible. Wow. That was unbelievable. Is everybody OK?

“Who’s the guy that threw that punch?” he continued. “You know, you reminded me of Evander, the real deal, Holyfield,” referring to the former heavyweight champion, who was also in attendance at the rally.

“You gotta give them credit. It takes courage to do that at a Trump rally,” he said. “He got whacked.”

The president was interrupted at least nine times by hecklers. One protester who was removed by security was followed by a rally attendee, who appeared to slap the demonstrator on the head.

Trump was in South Carolina to support Darline Graham, the sister of late senator Lindsey Graham who died suddenly in July from a heart condition. Graham, appointed to serve the remainder of her brother’s term, is facing Democratic challenger Annie Andrews in her bid for a full six-year term.

Related: ‘Man, I loved that’: Trump cheers South Carolina rally attender who hit protester

Updated

Responding to the ad on Wednesday, Amy Acton told a group of voters that her mother was not well and Ramaswamy shouldn’t have “exploited her”.

Earlier in the week, her brother had called Vivek Ramaswamy’s attack ad a “despicable low” in a statement released by Acton’s campaign:

It’s not surprising that Vivek Ramaswamy has stooped to such a despicable low as to attempt to turn the sexual abuse Amy endured at twelve years old from our birth mother’s husband into a political talking point.

After he was arrested and Amy and I were removed from their custody, our birth mother stayed married to Amy’s rapist until he died. This desperate, disgusting attack reveals exactly who Vivek Ramaswamy is at his core – a pathetic excuse for a man who is willing to hurt anyone as long as it gets him what he wants.”

The ad, which had circulated among conservatives on social media, featured Acton’s mother, Donna Arthur, urging Ohioans to not vote for her daughter.

The Ohio gubernatorial campaign between Acton and Ramaswamy is regarded as one of the uglier contests in the 3 November midterm elections.

Acton has refused to debate Ramaswamy, who she has called a “chronic liar” and has also criticized him for airing an ad that features a woman married to a registered sex offender.

Updated

Vivek Ramaswamy campaign ad for Ohio ‘shameful, disgusting’, says Republican congresswoman

Good morning and welcome to our live coverage of US politics. We’re less than two weeks out from the midterm vote and the campaigns are getting even more nasty.

Condemnation continues of Republican Vivek Ramaswamy’s campaign in the Ohio governor race after his team put out an attack ad, featuring the estranged mother of his Democratic rival Amy Acton criticising her daughter and calling her a liar.

Acton’s campaign has called it a despicable ad after putting out the clarification that Acton was sexually abused by her stepfather and removed from her mother’s custody at age 12.

Ramaswamy’s team, however, has dug in behind the ad, and were backed by JD Vance on Wednesday, who condemned Republican criticism. He said Ramaswamy “had the audacity to run a TV commercial which calls ​it out like it is”.

However, the South Carolina congresswoman Nancy Mace joined the chorus of Republican critics, saying:

This ad is going to go down as the most shameful, disgusting, offensive ad this election season.

She said she was stunned, adding:

I just can’t believe that this is what passes for decency in this election.

Stay with us for more developments.

Updated