Two U.S. Olympic swimmers were prevented from leaving Brazil on Wednesday night as differences emerged in their accounts of an armed robbery they said they endured last weekend.

The U.S. Olympic Committee said Wednesday evening that swimmers Jack Conger and Gunnar Bentz were removed from their return flight to the United States by Brazilian authorities.

Early Thursday, the USOC released a statement indicating that Conger and Bentz were no longer being detained but were not yet free to leave the country.

According to the statement: "Jack Conger and Gunnar Bentz were detained Wednesday night shortly before their flight was scheduled to depart from Rio. They were released by local authorities with the understanding that they would continue their discussions about the incident on Thursday. James Feigen is also communicating with local authorities and intends to make further statements regarding the incident on Thursday as well.”

Bentz and Conger, a three-time All-Met swimmer of the year from Good Counsel High School, were pictured by Brazil’s TV Globo entering a police office at Rio de Janeiro’s international airport with their carry-on luggage, but they did not comment to a reporter. The O Globo newspaper reported that the swimmers had boarded United Airlines Flight 128 to Houston and that two representatives from the U.S. Consulate and one from the USOC had arrived at the airport to accompany them.

Earlier Wednesday, a Brazilian judge ruled that the passports of fellow swimmers Feigen and Ryan Lochte should be seized after discrepancies emerged in their accounts of what transpired in early Sunday, after the four athletes left a dance party at the Club France official Olympic hospitality venue.

Judge Keyla Blanc de Cnop, from a special magistrate court set up for big sporting events, ruled that there were “possible divergences” in the versions of the robbery that the swimmers gave police.

In a statement released on the court’s website Wednesday, Blanc de Cnop said that in Lochte’s testimony to police, he said the athletes were stopped early Sunday by one robber who demanded all their money: $400. Blanc de Cnop said that Feigen, however, told police that the athletes were surprised by multiple robbers but that only one was armed.

Brazil’s G1 news site reported later Wednesday that another judge had ordered that Conger’s and Bentz’s passports also be seized. That court decision had not been released as of late Wednesday.

Security footage published Wednesday by the Daily Mail showed the men arriving at Rio de Janeiro’s Athletes’ Village appearing unfazed after the alleged incident. Brazilans have reacted with anger to what many perceived as a false account of a robbery and began conjecturing over what might have happened.

Lochte’s lawyer Jeff Ostrow told The Post that his client was already back in the United States.

The State Department acknowledged the developments Wednesday night.

“We have seen media reports that two U.S. citizen athletes were detained,” State Department spokesman John Kirby said. “We stand ready to provide all appropriate consular assistance. Due to privacy considerations, we do not have any further information to offer. We refer you to Brazilian authorities for more information about this case.”

News of the robbery broke Sunday, and confusion soon followed. A spokesman for the International Olympic Committee initially said the report of a robbery was “absolutely not true.” The spokesman later reversed himself, apologized and attributed the erroneous denial to information the IOC had been given by the USOC.

Lochte later told USA Today that he and the other swimmers did not immediately tell the USOC about the incident because “we were afraid we’d get in trouble.”

The swimmers had been at a birthday celebration and dance party at Club France, an Olympic hospitality venue beside the Rodrigo de Freitas Lagoon, with Thiago Pereira, a Brazilian swimmer, and Pereira’s wife, Gabriela Pauletti. Pereira and Pauletti left the party before the Americans, who told police that they caught a taxi at a nearby gas station.

Lochte told NBC that he and three other swimmers, including Feigen, were robbed when their taxi was stopped. The others were made to lie on the ground, but Lochte said he refused.

“And then the guy pulled out his gun, he cocked it, put it to my forehead, and he said, ‘Get down,’ and I put my hands up. I was like, ‘Whatever,’ ” he said.

Another doubt highlighted by the Brazilian judge concerns the time at which the swimmers reached the Athletes’ Village. The footage obtained by the Daily Mail shows them passing through a security check just before 7 a.m. — at least four hours after they were supposed to have left the party. In the footage, Lochte jokingly hits Feigen over the head with his Olympic credential.

“It was perceived that the supposed victims arrived with their physical and psychological integrity unshaken, even making jokes with each other,” the judge said, according to the court statement.

During NBC’s Olympic broadcast Wednesday night, host Matt Lauer told anchor Bob Costas of a telephone interview he said he had with Lochte on Wednesday. Lauer said Lochte was steadfast in saying the robbery took place and denied the notion that the swimmers had concocted a story to cover for some other behavior. Lauer said Lochte did alter two details from his earlier account, now saying their taxi had not been pulled over but had never left the gas station and that the gun had been pointed in his direction but not pressed to his forehead.

Ostrow confirmed that his client is in the United States.

“Ryan left the country after his events, after fully meeting with the Brazilian authorities, the State Department, the FBI — everybody who wanted to meet with him,” Ostrow said. “He made himself available and provided the Brazil police with a statement. He wasn’t told to stay around or that [the authorities] had other questions, but we told them we were still available if they had further questions. He was planning on leaving, and he left. I don’t know what they’re trying to do down there. If they need to get in touch with me, we have always been fully cooperating. Nobody has reached out to me. Nobody has reached out to Ryan.”

Ostrow also said that the incident happened “exactly the way Ryan described it” under oath to Brazilian police and that he believes Lochte’s account of the incident to the police was the same as the one he told on the “Today” show.

“They were robbed at gunpoint — the way he described it,” Ostrow said.

The San Antonio Express-News reported that Feigen, still in Brazil, declined to comment when contacted by the newspaper.

“I can’t talk right now,” Feigen said. “I’m still in Brazil, and [an interview] is going to have to wait.”

Carol Morello contributed from Washington.