British comedian and actor Russell Brand has been accused of rape, sexual assaults and emotional abuse during a seven-year period, according to the results of a media investigation published Saturday.

Four women have alleged sexual assaults between 2006 and 2013 when Brand was at the height of his fame working as a presenter for BBC Radio 2, Channel 4 and acting in Hollywood movies, a newspaper said.

The allegations, which Brand denies, were made in a joint investigation by The Sunday Times, the Times and Channel 4 Dispatches.

According to the investigation, published in the Sunday Times, others have made a range of accusations about Brand's controlling, abusive and predatory behaviour.

In a video released on Friday, Brand, 48, denied the "very serious criminal allegations" that he said would be made against him.

He said he received letters from a TV company and a newspaper listing "a litany of extremely egregious and aggressive attacks".

"Amidst this litany of astonishing rather baroque attacks are some very serious allegations that I absolutely refute," he said in the video clip posted online.

He said, "These allegations pertain to the time when I was working in the mainstream, when I was in the newspapers all the time when I was in the movies, and as I've written about extensively in my books, I was very, very promiscuous".

He added that "during that time of promiscuity, the relationships I had were absolutely, always consensual". According to the media findings, one woman alleged Brand raped her in his Los Angeles home while another claims he assaulted her during a three-month relationship while she was 16 and still at school.

Known internationally as the former husband of pop star Katy Perry, Brand began his career as a stand-up comedian in the early 2000s. He was the host of chat show Big Brother's Big Mouth, a spin-off of the popular reality series, for three years from 2004. He also played rock star Aldous Snow in the 2008 film "Forgetting Sarah Marshall" and its 2010 sequel "Get Him To The Greek".