Former Wollongong motorcycle world champion Wayne Gardner and his son Remy remain in custody in Japan following an alleged road rage incident before the Montegi MotoGP race at the weekend.
The Department of Foreign Affairs and Trade said it was providing consular assistance to "two Australian men arrested in Japan", following an alleged crash and scuffle outside the Twin Ring Montegi circuit, about 150 kilometres north-east of Tokyo, on Sunday.
A department spokesperson said that, "due to our privacy obligations, we are unable to provide further information".
Remy, 18, was competing in Sunday's race and, on the morning of the event, was reportedly driving to the circuit with his father, 57, in the passenger seat.
Police allege there was a minor collision between the Gardners' car and another vehicle just outside the circuit about 8am.
The Gardners and three men in the other car got out of their vehicles, when Wayne is accused of starting to push the men and grabbing their collars. He denies the claim.
Wayne was arrested at the circuit, while Remy went on to compete in Sunday's event, finishing in 19th position. He was arrested the following day.
Fairfax Media has been unable to confirm reports that Remy was arrested for not holding an international driver's licence, which foreigners are legally required to carry.
A spokesman for Michael Hill Promotions, which represents Remy, said he had nothing to say about the alleged incident.
Fairfax Media has also contacted the Gardners for comment.
Following Sunday's race, Remy tweeted his result and wrote that he was moving on to his "home GP" at Phillip Island this weekend.
MotoGP commentator Keith Huewen said Remy had been replaced by Anthony West for the Australian Motorcycle Grand Prix.