US chat show host David Letterman has confessed during a recording of his show he has had sexual relationships with female members of his staff.
"I have had sex with women who work for me on this show," he told an audience in New York, saying an attempt had been made to blackmail him over the affairs.
Letterman said "a guy" had threatened to expose the relationships unless a payment of $2m (£1.2m) was made.
CBS, which broadcasts Letterman's show, said an employee had been arrested.
It said the man, who has not been officially named, works on the true-crime show 48 Hours and had been suspended pending the results of the investigation.
The man was arrested on Thursday on charges of attempted grand larceny, CBS said.
Letterman, 62, married long-term girlfriend Regina Lasko in March. They have a six-year-old son.
'Terrible things'
"I have a little story I have to tell you," announced Letterman on Thursday, saying he was first approached by the alleged blackmailer three weeks ago.
He said he had got in his car early one morning to find a package with a letter containing proof of the "terrible things" he was said to have done.
The letter, he said, was from a man who threatened to write a book and screenplay about the veteran broadcaster unless he was given money.
On the advice of his attorney, Letterman said, he had contacted prosecutors at the Manhattan District Attorney's Office.
As part of the investigation, he continued, he had issued a "phoney" $2m cheque to the person allegedly attempting to extort him.
"This morning I did something I've never done in my life," said the broadcaster. "I had to go downtown and testify before a grand jury."
In his testimony he acknowledged he had conducted sexual relationships with members of his staff.
"I had to tell them all of the creepy things that I had done," he said.
He did not say when the relationships took place or how long they lasted.
'Bizarre experience'
"The creepy stuff was that I have had sex with women who work for me on this show."
Letterman said it had been "a very bizarre experience" and that he did not "plan to say much more on this particular topic".
"I felt like I needed to protect these people," he said. "I need to protect my family. I need to protect myself [and] hope to protect my job."
David Letterman has presented The Late Show on CBS since 1993.
Prior to that he hosted a late-night talk show on rival network NBC.
After Letterman's comments, CBS said the presenter had addressed the issue during the show, and that it "believes his comments speak for themselves".