Several of US President-elect Donald Trump’s cabinet nominees are facing heavy scrutiny, including claims of misconduct.

His defence secretary pick Pete Hegseth denies a sexual assault allegation and potential attorney general Matt Gaetz is at the centre of an ethics investigation.

Trump's health secretary nominee, Robert F Kennedy Jr, is facing severe criticism for his vaccine scepticism.

Trump will need the US Senate to confirm these nominees when he takes office in January, and though the chamber will be controlled by his fellow Republicans, his cabinet contenders will face an intense grilling during bipartisan hearings.

On Friday, police said that Hegseth, the Pentagon nominee, had been investigated for an alleged sexual assault in California in 2017.

Hegseth, a Fox News host and veteran of the wars in Afghanistan and Iraq, was never arrested and denies wrongdoing.

Trump spokesman Steven Cheung said: “Mr Hegseth has vigorously denied any and all accusations, and no charges were filed.”

Meanwhile, the BBC’s US partner CBS reported that Hegseth had once been flagged as a potential "insider threat" by fellow military personnel who thought he had a white-supremacist tattoo.

Hegseth has denied any connection to extremist groups.

A former member of the Minnesota National Guard, he has a tattoo on his bicep reading “Deus Vult”, a latin phrase meaning “God wills it”, a rallying cry for Christian crusaders in the Middle Ages.

Retired Master Sgt DeRicko Gaither told CBS: “I looked it up and that tattoo had ties to extremist groups.” He said he had flagged the body ink to leadership.

US Vice-President-elect JD Vance rushed to Hegseth’s defence, saying the latin phrase is a nothing more than a Christian motto. He accused the Associated Press, which first reported the story on the tattoo, of "disgusting anti-Christian bigotry".

Hegseth was stopped from serving as an officer in Washington DC during President Joe Biden’s inauguration in 2021. In a book published earlier this year he said he was turned down for the duty because of his tattoos.

Meanwhile, Trump’s pick for attorney general, Matt Gaetz, is battling allegations of misconduct while he was a congressman.

He resigned from his Florida seat in the US House of Representatives on Thursday within hours of Trump nominating him to lead the US Department of Justice.

His exit halted the release of a congressional report into allegations of sexual misconduct, illicit drug use and misuse of campaign funds.

House Speaker Mike Johnson, a Republican, asked on Friday that the report remains under wraps as Gaetz is no longer a member of the body - even amid bipartisan requests that it be shared as part of his vetting for the role of a top prosecutor in the US.

Hours later, an attorney for two women who provided testimony to the House Ethics Committee about Gaetz urged lawmakers to release the panel's report.

The lawyer, Joe Leppard, told CBS that one of his clients had witnessed Gaetz having sex with an underage girl in Florida in 2017. Mr Leppard urged lawmakers to release the House Ethics Committee report.

However, the justice department last year investigated the allegations and declined to press charges against Gaetz.

He has previously denied claims he had sex with a 17-year-old while he was an adult at a party in Orlando.

The 42-year-old Florida lawmaker wrote on Friday on X that "lies were weaponised to try to destroy me".

Robert F Kennedy Jr, Trump's nominee to serve as the head of the US Department of Health and Human Services, is meanwhile facing backlash over his vaccine scepticism.

Shares in vaccine makers and healthcare firms around the world slid sharply on Friday, as investors reacted to the nomination of a campaigner who has vowed to crack down on “Big Pharma”.

The head of the American Public Health Association, which has a 25,000-strong membership of health professionals, told the BBC that Kennedy's criticism of immunisations had "already caused great damage in health in the country".

George C Benjamin added that Kennedy was "just absolutely the wrong guy for it".

Trump himself has so far not directly addressed the criticism of his picks.

The president-elect is still hiring for his incoming administration, with posts such as FBI director and treasury secretary yet to be named.