U.S. President Barack Obama laughs during the taping on his guest appearance on the Late Show with David Letterman show in New York, September 21, 2009. REUTERS/Kevin Lamarque

U.S. TV talk-show host David Letterman said on Thursday he was the victim of a $2 million extortion plot by a man who threatened to write a screenplay about Letterman having affairs with employees.

An employee of CBS's 48 Hours, a documentary show that regularly features true crimes, was arrested on Thursday in connection with the case, CBS said in a statement.

Letterman told his audience on CBS's Late Show with David Letterman that he found a package in his car three weeks ago from a person claiming to have information about his sexual affairs and demanding $2 million to avoid going public.

He quoted a note as saying: I know that you do some terrible, terrible things and I can prove that you do these terrible things.

Sure enough, contained in the package was stuff to prove that I do terrible things, Letterman added.

The 62-year-old, who was recently married, said that after consulting his attorney, he arranged to meet the man who said he planned to write a screenplay and a book about all the terrible stuff Letterman did unless he was paid off.

The creepy stuff was that I have had sex with women who work for me on this show, Letterman told a stunned audience, which seemed unsure how to react to the story, laughing and applauding at times and exclaiming at others.

My response to that is, yes I have, Letterman said. Would it be embarrassing if it were made public? Perhaps it would, especially for the women.

It's been a very bizarre experience. I feel like I need to protect these people. I need to certainly protect my family. I need to protect myself. I hope to protect my job, he said.

Letterman said he went to the Manhattan District Attorney's office. They said, 'Whoa, hello, this is blackmail,' Letterman said.

An investigation led to an arrest earlier on Thursday. As part of the investigation, Letterman said he handed over a phony check for $2 million to the individual.

There were no details on the identity of the suspect from the District Attorney's office or from Letterman himself.

CBS issued a statement saying an employee at 48 Hours was involved in the investigation and arrested on Thursday on charges of attempted grand larceny.

The employee has been suspended pending the results of the investigation, CBS said. Mr. Letterman addressed the issue during the show's broadcast this evening, and we believe his comments speak for themselves.

Letterman, who was married once before, is intensely private, and is rarely photographed with his family. He married longtime companion Regina Lasko in March. They have a son born in 2003.

Shortly after his wedding, he said on the show: I had avoided getting married pretty good for, like, 23 years, and I -- honestly, whether this happened or not -- I secretly felt that men who were married admired me ... like I was the last of the real gunslingers.

Known for his comic Top 10 lists on current events, Letterman has been hosting the Late Show since 1993 and has been a fixture on late night TV for nearly three decades. Just last week U.S. President Barack Obama appeared on the show.

Letterman started Thursday's broadcast with his regular monologue, which included references to the infidelity of politicians.