American Olympic swimmers Gunnar Bentz, left, and Jack Conger, center, were taken off their flight from Brazil to the U.S. on Wednesday by local authorities amid an investigation into a reported robbery.

RIO DE JANEIRO — Two American Olympic swimmers were taken off their flight from Brazil to the U.S. by local authorities amid an investigation into a reported robbery targeting 12-time medalist Ryan Lochte and his teammates.

A lawyer for the two athletes said today they will not be allowed to leave Brazil until they provide testimony to investigators, who are still searching for answers about how the swimmers were robbed Sunday morning.

Jack Conger and Gunnar Bentz left the Rio de Janeiro airport early today after being taken off the plane Wednesday. They departed for an unspecified location and had yet to testify, said attorney Sergio Viegas.

The action comes amid increasing tension between Brazilian authorities and the American swimmers over the ever-changing account of the robbery. Police say they have found little evidence so far to support their claims, and that the swimmers were unable to provide key details.

Lochte has said he was with Conger, Bentz and Jimmy Feigen when they were robbed at gunpoint in a taxi by men with a police badge as they returned to the athletes village from a party, several hours after the final Olympic swimming events were held.

Lochte has returned home to the U.S. Feigen, along with Conger and Bentz, remains in Brazil.

Lochte won a gold medal in Rio in a relay race alongside teammate Michael Phelps.

NBC reported Wednesday night that Lochte backed off some of his earlier claims about the robbery. He now says the taxi wasn’t pulled over by men with a badge, but that they were robbed after stopping at a gas station, NBC reported. Lochte also said the assailant pointed a gun at him rather than putting it to his head.