At least 39 people were injured, three of them seriously, when the floor of a local church filled with teens collapsed during a concert.

Police said about 1,000 youths were at the Central Heights Church in Abbotsford, British Columbia, to hear the Christian rock band Starfield when a large area in front of the stage gave way Friday night, sending people in the crowd falling several feet into the basement below.

By late evening, David Plug, a spokesman for the local health authority said 23 people were treated in the Abbotsford Regional Hospital, while hospitals in the nearby cities of Chilliwack, Mission and Langley treated 16 people between them.

"Most of the patients are minor fractures and similar injuries but there are some serious injuries and patients are still being assessed," said Plug.

Const. Casey Vinet of the Abbotsford police said when officers arrived at the scene, they saw a hole in the floor about 22 feet wide.

All available Abbotsford police, local Royal Canadian Mounted Police and ambulance crews were dispatched to the scene, Vinet said.

Vinet said investigators are now trying to determine what caused the collapse.

Witnesses said that the lighting system crashed onto the stage, but Vinet said he was not aware of that report.