A longtime CBS News producer has been indicted for allegedly attempting to extort $2 million from late night comedian David Letterman.

Manhattan District Attorney Robert Morgenthau announced the indictment Friday against Robert (Joe) Halderman, a 51-year-old producer of the true-crime show “48 Hours." Halderman, of Connecticut, is charged with one count of attempted grand larceny. If convicted, he could face up to 15 years in prison.

The alleged attempt, which took place last month, led the married Letterman to announce to his "Late Show" studio audience and millions of viewers Thursday that he had engaged in sexual relationships with female members of his staff.

According to Morgenthau, an investigation by the Manhattan District Attorney's office revealed that Halderman waited outside of Letterman's home at 6 a.m. on Sept. 9 to deliver a package of embarrassing e-mails and photographic proof of the affairs to the comedian inside his limousine. Letterman said Halderman threatened to release a screenplay that would ruin his reputation.

An unidentified attorney for Letterman subsequently took the evidence to the prosecutor's office, which set up an undercover sting at a hotel. Three additional meetings took place, which were recorded by the attorney under the guidance of New York police detectives. On Sept. 30, Halderman was presented with a phony check for $2 million, which he deposited in his bank account.

Halderman's fellow employees expressed surprise at the veteran producer's arrest Thursday.

“Everyone there has worked with him,” CBS staffers told FOXNews.com of Halderman. “He’s a big deal there. He’s directed news specials that the CBS documentary team has produced, 9/11 stuff, Olympics, just about every big story."

Sources tell FOXNews.com that the nature of Halderman’s assignments would likely have given him access to loads of sensitive information over the years.

Phone calls to Halderman were not returned Friday.

According to a report from MyFOXNY, the woman at the center of the scandal is Halderman's girlfriend and Letterman's former assistant, Stephanie Birkitt. The details of the alleged affair — which reportedly went on for years — were outlined in her diary and through personal correspondence, MyFOXNY reports.

According to a report from TMZ.com, Halderman's divorce papers stipulated that he pay a substantial amount of child and spousal support — nearly $6,000 — each month for three years. According to the District Attorney's investigation, Halderman told Letterman that he needed to "make a large chunk of money."

Letterman said that "this whole thing has been quite scary." But he mixed in jokes while outlining what had happened to him, seeming to confuse a laughing audience at Thursday's taping about whether the story was true.

Click here for a clip of Letterman addressing the affairs, extortion.

Letterman's "Late Show" audience was the first to hear the story, which came as a shock since the 62-year-old Letterman had married longtime girlfriend Regina Lasko in March. The couple began dating in 1986 and have a son, Harry, born in November 2003. Fatherhood and his heart surgery in 2000 had seemed to mellow Letterman, who took over as the most popular late-night comedy host this summer after NBC replaced Jay Leno with Conan O'Brien on the "Tonight" show.

Letterman sat behind his desk to outline the scheme after a monologue that targeted some frequent foils like Sarah Palin and Dick Cheney.

Three weeks ago, Letterman said he got in his car early in the morning and found a package with a letter saying, "I know that you do some terrible, terrible things and that I can prove that you do some terrible things." He acknowledged the letter contained proof.

He said it was terrifying "because there's something insidious about (it). Is he standing down there? Is he hiding under the car? Am I going to get a tap on the shoulder?"

He told the audience that he had to testify before a grand jury on Thursday.

"I was worried for myself, I was worried for my family," he said. "I felt menaced by this, and I had to tell them all of the creepy things that I had done."

He said "the creepy stuff was that I have had sex with women who work for me on this show. My response to that is yes, I have. Would it be embarrassing if it were made public? Yes, it would, especially for the women."

Whether they wanted to make the relationships public was up to them, he said.

"It's been a very bizarre experience," he said. "I felt like I needed to protect these people. I need to protect my family. I need to protect myself. Hope to protect my job."

CBS said in a statement that "we believe his comments speak for themselves."

Perhaps as a defense mechanism, Letterman sprinkled his remarks with jokes: "I know what you're saying," he said. "I'll be darned, Dave had sex."

He said he wouldn't talk further about it, and recited a Top Ten list. But it wasn't far from his mind. During banter with actor guest Woody Harrelson, Letterman said, "I've got my own problems."

It was not immediately clear when the relationships took place or how long they lasted. Letterman's "Late Show" has been on the air since 1993. Before that, "Late Night with David Letterman" aired on NBC from 1982 to 1993.

Letterman won't be taping a show Friday. Friday night's show was taped Thursday.

Alicia Maxey Greene, a spokeswoman for the Manhattan District Attorney's office, declined to comment.

It's the second set of embarrassing headlines for Letterman in four months. In June, he apologized to Palin for making a crude joke about the former Republican vice presidential candidate's 14-year-old daughter. Although there was a small "fire Letterman" demonstration outside of his studio later, CBS stood by its late-night star.

Last fall Letterman sharply denounced Palin's running mate, John McCain, for abruptly canceling a "Late Show" appearance. Weeks of withering jokes by Letterman eventually forced McCain to come on the show and beg for forgiveness.

Letterman was also the victim of a 2005 plot by a former painter on his Montana ranch to kidnap his nanny and son for a $5 million ransom. The former painter, Kelly A. Frank, briefly escaped from prison in 2007 before being recaptured.

The Associated Press contributed to this report.

Click here for more on this story from MyFOXNY.