Police say up to 2,000 people were involved in a protest that turned into a riot at a tyre shop in Oakleigh in Melbourne's south-east.

Racing fans had gathered at the intersection of the Princes Highway and Warrigal Road to protest over the cancellation of the Easternats race meet.

They were targeting Bob Jane, the tyre company that sponsored the event.

Easternats organisers say Bob Jane cancelled the event after failing to finalise contract negotiations.

Police were called in about 11:30pm (AEDT) when the protest turned violent.

Acting Assistant Commissioner Neville Taylor says the event started peacefully, before people started smashing windows and damaging a car.

"At one particular time, some person decided it would be smart to throw a flare towards one of our police officers, and this has really sparked the riotous behaviour," he said.

"We had about 50 police units that were in attendance in response to this, and our aim was about dispelling that crowd, to maintain the community safety."

He says police have video footage of what happened.

"We've got some very good footage of that riot that took place there, so they'll be aiming to identify probably the key people who were involved in the actual behaviour in the riot, as well as the large crowd that was there," he said.

It is believed tyres and other items were also stolen.

Traffic was stopped at the intersection for two hours, and members of the air wing, dog squad and force response units were brought in to disperse the crowd.

No major injuries have been reported.

Police have called on those responsible to hand themselves in.