Singer Adam Diplock, 29 – who wowed the Britain’s Got Talent judges as part of swing band Jack Pack – has been quizzed by police over an allegation of grievous bodily harm against a female friend, reports the Mirror newspaper.

He voluntarily went to the police after the allegation was made.

He was not arrested and refused to comment on the allegations.

Adam, who used to date Saturdays singer Vanessa White, has vowed to friends that the incident – which is alleged to have taken place before his Britain’s Got Talent audition earlier in May – will not put him off his bid to win the show.

A source said: “As far as Adam’s concerned he has done nothing wrong. His focus is going all the way in the contest.”

Eight million viewers saw him perform as part of the four-member band. The group were voted through to the next round after impressing the judges with their version of Frank Sinatra’s That’s Life.

It’s not the first time that Adam has appeared in a TV talent contest. He made it through to the finals of the X Factor in 2007 as part of a band called Futureproof, which has since disbanded.

They played to 500,000 fans on the X Factor tour at venues such as Wembley and London’s O2, and also supported stars including Westlife, Sugababes, Sir Tom Jones, Boys II Men and Blue.

When the band split up, Adam went on to work as a wedding singer, and with his new bandmates Alfie Palmer, Andrew Bourn and Sean Ryder Wolf.

The foursome have come under fire for downplaying their musical backgrounds when they auditioned for Britain’s Got Talent.

Andrew, who claimed he fixed ovens for a living, and Alfie, who said he was a painter and decorator, were revealed to be professional Michael Bublé impersonators.

But Andrew said on the show: “We’ve not performed in public before. We’ve done the odd bit of singing in front of our parents, but this is it – it’s a big deal.”

Sean, who described himself as a full-time gardener, turns out to be a model and actor who appeared as Jamelia’s love interest in her music video No More.

A Britain’s Got Talent spokesman said of the police quizzing: “Adam has not been arrested. He was interviewed over an allegation after voluntarily meeting police.”

Click here for the latest Britain’s Got Talent auditions