Just one day before the finale of a documentary series about his life in which he appears to confess to killing, the strange and estranged son of one of New York City's most powerful real-estate families was arrested.

Robert Durst had checked into a New Orleans hotel when he was intercepted Saturday by F.B.I. agents investigating his role in the 2000 murder of his friend Susan Berman in Los Angeles. He has previously been investigated in the 1982 disappearance of his wife, Kathleen Durst, and the 2001 shooting and dismemberment of his neighbor Morris Black in Texas.  Durst was acquitted of murder in the death of Black after a trial in which he said he shot Black in self defense as the two struggled over a gun.

In the final episode of the HBO documentary “The Jinx: The Life and Deaths of Robert Durst,” Durst appears to admit to killing someone while off-camera but still wearing a microphone. The recording came after filmmakers confronted him with handwriting evidence that may link him to Berman's death. Durst is heard saying to himself, "That's it. You're caught," and "Killed them all, of course."

Jim Dwyer has written about Robert Durst for the New York Times. He said it's not clear whether the film clip was the trigger for the arrest. And as to why Durst would have agreed to the documentary in the first place, Dwyer says it was likely motivated by a need to prove himself.

"I think he wanted to show how clever he was." Dwyer said. "He's been the kind of runner-up brother in a very accomplished family, in some ways, and he's lived this extremely bizarre life where he did whatever he wanted whenever he wanted."