Investigators were trying to determine what caused the collapse. When officers arrived at the scene, they saw a hole in the floor about 22 feet wide, said Casey Vinet of the Abbotsford police.
David Plug, a spokesman for the local health authority said 23 people were treated at the Abbotsford Regional Hospital, while hospitals in nearby cities treated 16 others.
"Most of the patients are minor fractures and similar injuries but there are some serious injuries and patients are still being assessed," Plug said.
