Scotland Yard is investigating sex crime allegations against former BBC disc jockey Tim Westwood that go back 40 years, Sky News understands.
Detectives first received claims of sex assaults in April after the BBC aired a documentary revealing allegations against Westwood, 64, from seven women.
He strongly denied any wrongdoing.
Soon after, police began assessing more reports, including alleged assaults in London, Essex and Hertfordshire.
The BBC later reported allegations from another 10 women, one claiming she had begun having sex with Westwood after meeting him at a club when she was 14.
Scotland Yard has not named Westwood, but when asked about the allegations aired on the BBC, it said in a statement: "Detectives from the Met's Central Specialist Crime continue to investigate four reports relating to allegations of non-recent sexual offences allegedly committed by a man.
"The offences are alleged to have occurred in London in 1982, 1985, 2010 and 2016. There have been no arrests, enquiries continue."
The pioneering hip-hop DJ worked for BBC Radio One from 1994 to 2013 and has had a huge following as a club performer.
He stood down from his radio show on Capital Xtra in April when the BBC allegations emerged, with women alleging predatory and unwanted sexual behaviour and abuse of his position in the music industry.
This week, the BBC is expected to publish the findings of an internal enquiry into Westwood's career, prompted by its documentary based on an investigation by its own news reporters and the Guardian newspaper.
The day after the story broke in April, BBC director general Tim Davie said he had "seen no evidence of complaints", but the corporation later confirmed it had received six complaints of bullying and sexual misconduct, one of which it passed to the police at the time.