(CNN) -- Robert Durst, the scion of a multimillionaire developer charged with the murder of a close friend, appeared to be preparing anew for a life on the run when he was arrested in New Orleans, according to court documents: He had more than $40,000 in cash and a neck-to-head latex mask to alter his appearance.
The details emerged Wednesday in court documents supporting a search warrant for Durst's Houston home.
The revelations come as the latest twist in the Durst saga has the murder suspect confined to a Louisiana prison's mental health unit after being deemed a danger to himself.
Durst, 71, who court papers said has a net worth of about $1 million, had been been withdrawing large sums of money from various bank accounts, including daily withdrawals of $9,000 over 35 days since October.
It's been a whirlwind week in which Durst, the subject of HBO's true-crime documentary "The Jinx," has gone from a man battling suspicions that he killed three people to a frail 71-year-old on suicide watch.
Durst is being held on drug and weapons charges in Louisiana as he awaits extradition to Los Angeles to face charges in the killing of a woman who was a close friend more than 14 years ago.
FBI agents are also investigating whether Durst could be connected to other unsolved murder cases.
The agency is putting out a call to local authorities to examine cold cases in locations near where Durst lived over the past five decades, a U.S. law enforcement official said. Unsolved cases in Vermont, upstate New York, the San Francisco Bay area and Southern California are among those getting a new look.
$100 bills, mask and a loaded revolver
The FBI agent who arrested him Saturday at a New Orleans hotel approached from behind and said, "Mr. Durst?"
Although Durst had checked into the hotel under the name "Everette Ward" and carried a Texas ID card with that name, he turned around when the agent called him by name, according to court documents.
In his hotel room, agents found more than $40,000 in cash, mostly in $100 bills packed into small envelopes, a loaded revolver, the rubber mask that covers the head and neck, his actual birth certificate and passport, and marijuana.
In his Houston apartment, authorities seized compact discs, bank statements, handwritten notes, credit cards and checks, stationary, a cell phone, boxes of court documents, photos and a trash bag of court transcripts. They also took three books about the disappearance of Durst's wife and his legal troubles, including "Without a Trace" and "A Deadly Secret."
On Tuesday, an appeals court granted a request from the Orleans Parish Sheriff's Office to move Durst to the Elayn Hunt Correctional Center's mental health unit in St. Gabriel, about an hour's drive from New Orleans. Lawyers for the Sheriff's Office argued that the jail where Durst was being held until Tuesday night can't accommodate inmates with acute mental health conditions. The appeals court agreed.
Durst's lawyer Dick DeGuerin said he "did not believe" his client was mentally ill, and that he should remain in Orleans Parish to give the legal team better access to him before a evidentiary hearing scheduled for Monday.
One day after he was charged with first-degree murder, police on Monday searched Durst's home in Houston, DeGuerin confirmed.
Durst owns three units in the 14th-floor condominium where he has has lived for many years.
He was arrested in New Orleans the day before the final episode of "The Jinx" aired on Sunday.
The episode included a recording of Durst apparently talking to himself in a bathroom: "What the hell did I do? Killed them all, of course," he is heard saying.
The Los Angeles County district attorney filed a first-degree murder charge against him Monday, accusing Durst of shooting and killing Susan Berman in December 2000. If convicted, he could face the death penalty.
"I think it's ridiculous for them to be making a search 15 years after Susan Berman was killed, and they're searching a place in Houston," DeGuerin told CNN.
DeGuerin has said it's no coincidence authorities arrested Durst the day before the HBO documentary's final episode aired. He said he wasn't surprised about the search of his Texas condo, either.
"They're acting like a bunch of Keystone Kops, particularly after being embarrassed by the TV program," he said. "And I'll be even more surprised if they find anything of any evidentiary value whatsoever."
A neighbor told KTRK she saw Durst leave the Houston condo with two suitcases last week -- when he departed for New Orleans -- and that his assistant came several days later and took most of his belongings.
Attorney: Trial would end 'rumor and speculation'
Berman was shot in the head in her Beverly Hills, California, home in December 2000 shortly before investigators were set to speak with her about the disappearance of Durst's first wife, Kathleen McCormack Durst, in 1982.
Prosecutors accuse Durst of "lying in wait" and killing Berman, a crime writer and his longtime confidante, because she had information about a crime.
Durst has long maintained he had nothing to do with Berman's death or his wife's disappearance, though some have questioned whether the comments he makes at the end of "The Jinx" -- he apparently is oblivious to the "hot" wireless mic he was still wearing -- could be interpreted as a confession.
In the documentary, the handwriting in an anonymous letter to police telling them there was a "cadaver" in Berman's home is similar to the writing in a newly discovered letter from Durst that Berman's stepson found among her possessions. In both letters, Beverly Hills is misspelled as "Beverley."
The court paper in Houston said that four forensic experts concluded that the "cadaver" letter, which was postmarked the day before Berman's body was found, was likely written by Durst.
In the documentary, Durst said only Berman's killer could have written the "cadaver" letter.
In addition, court documents mention another anonymous letter, sent from New York in January 2001, to a Los Angeles police detective. It was titled "Possible motive for Susan Berman murder" and stated that Berman suspected Durst of being involved in his wife's disappearance. It also said Durst planned to visit Berman around the time of her death.
In a 2003 murder trial, Durst admitted he'd killed neighbor Morris Black in Galveston, Texas, and chopped up the body. He was acquitted after his attorneys argued he had acted in self-defense, though he later served nine months in prison on felony weapons charges stemming from that case.
DeGuerin told reporters Monday that his client didn't kill Berman.
"He's ready to end all the rumor and speculation and have a trial," DeGuerin said.
It's not clear when a trial would take place.
Durst waived his right to fight extradition to Los Angeles, but because prosecutors in New Orleans are pursuing charges against him, he remains jailed there.
Investigators believe he planned to travel from New Orleans to Cuba, a law enforcement official told CNN.
Investigators found a .38-caliber Smith & Wesson revolver and about 147 grams (5.2 ounces) of marijuana in Durst's hotel room in New Orleans, according to court documents. He was booked on charges of possession of a firearm by a convicted felon and possession of a firearm in the presence of a controlled dangerous substance.
Court documents filed Tuesday say Durst will receive medications while imprisoned, "including but not limited to hydrocodone as needed for pain."
CNN's Evan Perez, Chandler Friedman, Catherine E. Shoichet, Dave Alsup, Holly Yan, Chris Welch, Shimon Prokupecz and Kevin Conlon contributed to this report.
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