Police are looking to speak to witnesses to a so-called "hoon meet" involving hundreds of people in Melbourne's south-east, where rocks were thrown at police.
Videos uploaded to social media show a large crowd of people blocking off Marine Parade in St Kilda, watching cars do burnouts and playing loud music.
In a statement, Victoria Police said officers arrived at the area about 10:50pm on Thursday and discovered people had blocked off the street.
"While officers were making initial assessments of the crowd, a number of people advanced on Highway Patrol members," the police statement said.
Police used OC spray on the crowd, and someone damaged a police car and threw rocks, it said.
'We came out in the middle of a mob'
One witness, John, told ABC Radio Melbourne he was on his way home from a dinner party about 11:00pm when he saw police redirecting traffic through local streets and back onto Marine Parade.
"We came out in the middle of a mob," he said, comparing the situation to the Cronulla Riots.
"It was unbelievable, we were just surrounded by people."
He said some in the crowd were wielding "makeshift clubs" and seemed to be agitating for a fight.
He said the main element was the cars.
"Lots of cars, cars going in the wrong direction, white utes and driving all around, cars were going in all directions," he said.
Police are calling for anyone with information or dashcam footage to contact Crime Stoppers.
