Rowdy crowds took to the streets of Los Angeles after the Dodgers won the World Series, setting a city bus on fire, breaking into stores and setting off fireworks. A dozen arrests were reported by police Thursday.

Video showed people throwing objects at police in Los Angeles as sirens blared and officers told them to leave the area after the Dodgers defeated the Yankees in Game 5 in New York.

Other video showed revellers standing atop a bus waving a Dodgers banner and people running from a boarded-up Nike store with armfuls of sneakers before throwing the merchandise into cars parked outside. No injuries were reported.

"As we celebrate this achievement tonight and in the coming days, violence will not be tolerated," Mayor Karen Bass said in a statement. The mayor said the Los Angeles Police Department will be on high alert throughout the week to protect communities and businesses in the city, which has been the site of previous unrest after championship wins by both the Lakers and the Dodgers.

There were some "unruly, and at times violent and hostile celebrations" after Wednesday's win, with several acts of vandalism, including the burning of a Metropolitan Transportation Authority bus, LAPD spokesperson Officer Drake Madison said in an email. An email seeking details was sent to the transportation authority.

Arrests were on charges such as failure to disperse, receiving stolen property or commercial burglary, Madison said. There were also several instances of street takeovers downtown and police used less-lethal munitions to control several hostile and violent crowds, Madison said. In the coming days, detectives will attempt to identify those responsible for crimes, he said.

The Dodgers plan to commemorate their World Series championship Friday with a downtown parade followed by a celebration at Dodger Stadium. The team said Wednesday because of logistics, traffic and timing, fans won't be able to attend both events.

The parade was expected to include members of the Dodgers travelling atop double-decker buses along a 45-minute route on city streets.

Bass planned a Thursday morning news conference to discuss logistics for the celebrations.