A photographer takes a photo of the new waxwork figure of Russell Brand as it is unveiled at Madame Tussaud's on Monday, Oct. 11, 2010, in north London. (AP)

On Sunday, both the BBC and Channel 4, previous employers of British actor and comedian Russell Brand, announced that they are launching investigations into allegations of rape, sexual assaults, and emotional abuse spanning a seven-year period.

The 48-year-old Brand has denied these allegations.

Four women have come forward with claims of sexual assaults that occurred between 2006 and 2013, a time when Brand was at the peak of his career, working as a presenter for BBC Radio 2, Channel 4, and appearing in Hollywood movies. These allegations were revealed in a joint media investigation conducted by The Sunday Times, the Times, and Channel 4 Dispatches.

Both the BBC and Channel 4, as well as the production company Banijay UK, have pledged to initiate internal inquiries into these allegations. A BBC spokesperson stated, "We are urgently looking into the issues raised."

According to reports, multiple women have made various accusations about Brand's purported controlling, abusive, and predatory behavior. In response, Brand released a video on Friday in which he denied the "very serious criminal allegations" and mentioned receiving letters from a TV company and a newspaper listing a range of accusations. He stated that he absolutely refutes the serious allegations.

The media reports detail one woman's claim that Brand raped her at his Los Angeles residence, while another alleges he assaulted her during a three-month relationship when she was 16 and still in school.

Russell Brand initially began his career as a stand-up comedian in the early 2000s. He hosted the chat show "Big Brother's Big Mouth" for three years starting in 2004, and portrayed rock star Aldous Snow in the film "Forgetting Sarah Marshall" (2008) and its sequel "Get Him To The Greek" (2010).

The Metropolitan Police in London confirmed their awareness of the allegations but noted that they had not received any reports related to them. They encouraged anyone who believes they have been a victim of sexual assault, regardless of when it occurred, to contact the police.