Niagara Regional Police say several thousand people pushed through the fences at a free Billy Talent concert in Port Colborne, Ont., on Saturday.

Municipal officials say the venue at H. H. Knoll Park had reached capacity just before 9:30 p.m., at which point police decided to close the surrounding fences.

Police say in a statement today that a crowd of about 4,000 to 5,000 people outside the fences then pushed through the perimeter, challenging officers and security guards and leaving one officer with minor injuries.

The City of Port Colborne says about 15 minor injuries were reported among the concertgoers, and organizers decided to shut down alcohol service in the interest of public safety.