Former Radio 1 DJ Dave Lee Travis has been arrested as part of the police probe set up in the wake of the Jimmy Savile scandal, the BBC understands.
The 67-year-old was arrested at his home in Mentmore, Buckinghamshire, on suspicion of sexual offences.
He was bailed on Thursday evening to return in early January, police said.
The Met said their investigation into alleged abuse by Savile and others – Operation Yewtree – had so far recorded 200 allegations of sexual assault.
They have now identified about 450 potential victims of sexual abuse.
The arrest of Mr Travis is the fourth so far in connection with the Savile investigation.
In a statement, the Met said the latest arrest “falls under the strand of the investigation we have termed ‘Others'”, meaning the allegations are unrelated to Savile.
But the force said that the “vast majority” of the 450 possible victims were alleging sexual abuse by former BBC TV presenter and DJ Savile, who died last year aged 84.
Mr Travis has not been officially named by police, who made the arrest at 07:45 GMT. He was released on bail late on Thursday.
The DJ – known by the nicknames DLT and the Hairy Cornflake – is best known for his 25-year stint on Radio 1.
