Comedian and actor Russell Brand has been accused of rape, sexual assaults and emotional abuse during a seven-year period at the height of his fame.
The allegations were made in a joint investigation by the Sunday Times, the Times and Channel 4's Dispatches.
Four women are alleging sexual assaults between 2006 and 2013.
Brand has denied the allegations and said his relationships have been "always consensual".
During the years covered by the allegations, Brand had various high-profile jobs at different times, including at BBC Radio 2 and Channel 4, and as an actor in Hollywood films.
Other claims made as part of the investigation relate to Brand's allegedly controlling, abusive and predatory behaviour.
The investigation is published in the Sunday Times, while the Dispatches documentary, Russell Brand - In Plain Sight, aired on Channel 4 on Saturday.
Within hours of the allegations being published, Brand performed a scheduled comedy gig at the 2,000-capacity Troubadour Wembley Park Theatre in north-west London, as part of his Bipolarisation tour.
During the set, which lasted about an hour, Brand alluded to the accusations but did not address them directly. He told the audience there were things he wanted to talk about but could not.
Several women have made allegations against Brand as part of the investigation:
- One woman alleges that Brand raped her against a wall in his Los Angeles home. She was treated at a rape crisis centre on the same day. The Times says it has seen medical records to support this
- A second woman alleges that Brand assaulted her when he was in his early 30s and she was 16 and still at school. She alleges he referred to her as "the child" during an emotionally abusive and controlling relationship
- A third woman claims that Brand sexually assaulted her while she worked with him in Los Angeles, and that he threatened to take legal action if she told anyone else about her allegation
- The fourth woman alleged being sexually assaulted by Brand and him being physically and emotionally abusive towards her
On Friday, Brand released a video in which he denied "serious criminal allegations" he said were about to be made against him.
The actor and comedian said he had received letters from a TV company and newspaper, containing "a litany" of "aggressive attacks".
In the video, posted on YouTube and X, formerly known as Twitter, Brand said: "Amidst this litany of astonishing, rather baroque attacks are some very serious allegations that I absolutely refute.
"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.
"Now during that time of promiscuity the relationships I had were absolutely, always consensual."
Brand said he believed he was the subject of a "co-ordinated attack" and he was going to look into the matter because it was "very, very serious".
While not referring to the comedian by name, the Metropolitan Police said it was "aware of media reporting of a series of allegations of sexual assault" but had not received any reports.
"If anyone believes they have been the victim of a sexual assault, no matter how long ago it happened, we would encourage them to contact police."
The Sunday Times said all the women felt ready to speak only after being approached by reporters. The newspaper said several felt compelled to do so given Brand's newfound prominence as an online wellness influencer.
Most of the women, who the Times said do not know each other, have chosen to remain anonymous.
The Sunday Times said it gave Brand eight days within which to reply to detailed allegations, and when given further opportunity to respond, Brand published his response video on his YouTube channel.
The woman who said she was 16 when she first came into contact with Brand told the Sunday Times: "Russell engaged in the behaviours of a groomer, looking back, but I didn't even know what that was then, or what that looked like."
Another woman alleged to the newspaper that she repeatedly told Brand to get off her during one sexual assault, and that when he eventually relented he "flipped" and was "super angry".
A different woman claimed that Brand pushed her up against the wall and raped her, without a condom. She alleged Brand tried to stop her leaving until she told him she was going to the bathroom.
"I ran out and I jumped in my car - thank God I didn't park in his driveway - and booked it out of there," she said.
Brand has hosted a number of radio and TV programmes for networks including Channel 4, MTV, Radio X and the BBC.
He started his career as a stand-up comedian in the early 2000s but got his big break a few years later as the host of Big Brother's Big Mouth on E4.
After his profile surged, Brand was cast in Hollywood films such as Forgetting Sarah Marshall, Get Him To The Greek and Arthur.
The woman who said she was 16 when she met Brand told the Times she took her allegations to his literary agent Angharad Wood, the co-founder of Tavistock Wood, owned by Curtis Brown, in 2020.
Tavistock Wood told the BBC: "Russell Brand categorically and vehemently denied the allegation made in 2020, but we now believe we were horribly misled by him. Tavistock Wood has terminated all professional ties to Brand."
A Channel 4 spokesman told BBC News: "Channel 4 is appalled to learn of these deeply troubling allegations, including behaviour alleged to have taken place on programmes made for Channel 4 between 2004 and 2007.
"We are determined to understand the full nature of what went on. We have carried out extensive document searches and have found no evidence to suggest the alleged incidents were brought to the attention of Channel 4.
"We will continue to review this in light of any further information we receive, including the accounts of those affected individuals. We will be asking the production company who produced the programmes for Channel 4 to investigate these allegations and report their findings properly and satisfactorily to us."
It said that in recent years there had been extensive change in Channel 4's management and it was committed to ensuring the TV industry is safe and inclusive.
The relationship with the 16-year-old is alleged to have taken place at a time when Brand was working as a presenter on BBC Radio 6 Music.
It is alleged Brand would undress in the studio while working on the show. Dispatches also said Brand made a series of sexual remarks on air about a newsreader, which he later implied he had been told by BBC production staff to apologise for.
The Times added sources had told the newspaper that a complaint was made to BBC management about an "alarming display of aggression and disrespect" from Brand.
A BBC spokesman said: "Russell Brand worked for a number of different organisations, of which the BBC was one. As is well known, Russell Brand left the BBC after a serious editorial breach in 2008 - as did the then-controller of Radio 2.
"The circumstances of the breach were reviewed in detail at the time. We hope that demonstrates that the BBC takes issues seriously and is prepared to act.
"Indeed, the BBC has, over successive years, evolved its approach to how it manages talent and how it deals with complaints or issues raised.
"We have clear expectations around conduct at work. These are set out in employment contracts, the BBC Values, the BBC code of conduct and the anti-bullying and harassment policy.
"We will always listen to people if they come forward with any concerns, on any issue related to any individual working at the BBC, past or present."