Jailers moved erratic accused killer Robert Durst into a mental ward Tuesday night after the Sheriff’s Office in New Orleans argued that he has an “acute mental condition.”

The 71-year-old scion to a New York real-estate fortune was sent to the Elayn Hunt Correctional Center in St. Gabriel, La., which has a mental-health facility, after a day of legal wrangling over where he should be held.

The Orleans Parrish Sheriff’s Department asked a lower court for permission to move him to a psych ward, but was denied early in the day. But an appeals court later overruled the decision.

“It’s well established. I won’t say it here, but it’s an acute mental status,” Blake Arcuri, a lawyer for the Sheriff’s Office, said in arguing for the transfer. “He can ­receive the treatment he needs.”

Defense lawyer Dick DeGuerin, however, said “there is no acute mental illness that I’m aware of. I can converse with him very well. He is not incompetent, and his competency is not in question.”

The lower-court judge agreed he was not crazy, but was overruled, and Durst was relocated as investigators raided his condominium in a 17-story building in a posh Houston neighborhood.

Authorities were seen carrying away two boxes from the residence but it was not clear why the search was conducted.

Although Durst has waived extradition, he continues to wait in New Orleans as Los Angeles prosecutors are in no rush to put him on trial for the 2000 murder of his friend Susan Berman.

New Orleans authorities will first prosecute him on gun charges that could carry a sentence of 10 to 20 years.

Durst was busted Saturday — on the eve of the final episode of an HBO documentary, “Jinx,” about his life — in the Big Easy on an LA warrant for the Berman murder, and he also got slapped with local charges late Monday for keeping an unlicensed .38-caliber Smith & Wesson revolver.

“The fact that he was arrested with an unlicensed firearm bolsters LA’s case [because] Berman was shot to death. Secondly, it gives LA time to put their case ­together,” a source said.

A source in the Los Angeles District Attorney’s Office said prosecutors were loath to press for Durst’s transfer because of the missteps that foiled the 2010 extradition of movie director Roman Polanski from Switzerland to face charges he raped and sodomized a 13-year-old girl in 1977, the source said.

The source also noted that DA Jackie Lacey — a rising Democratic star and friend of President Obama — is “laser-focused” on the Durst case and doesn’t want a “repeat of the embarrassing O.J. Simpson trial.”

Durst — who beat the rap in the 2001 shooting and dismemberment of a Galveston, Texas, rooming-house neighbor — had long been suspected in the Dec. 23, 2000, fatal shooting of Berman.

She had served as Durst’s spokesman after the 1982 disappearance of his wife, Kathie, and Westchester authorities re-investigating that case wanted to interview Berman at the time of her death.

Meanwhile, Durst’s brother, Douglas, revealed in a newly released New York Times interview that he kept a piece of pipe in his office in the early ’90s to protect himself from Robert, who would keep a “sharp-pointed plumber’s wrench on his desk” as well.

Additional reporting by Kate Sheehy