VICTORIA -- Police say a fire that forced the two-day closure of a Chemainus high school is now being investigated as suspicious.

Students were forced to flee Chemainus Secondary School Thursday morning after a fire broke out in a second-storey student bathroom.

Firefighters from Chemainus, Crofton and Ladysmith were able to get the blaze under control but not before smoke filled classrooms and hallways.

"Due to the large amount of smoke still present, it wasn’t until later in the day that the RCMP and fire inspectors could check out the location of the fire," the Cowichan Valley School District said in a statement. "It was then that they determined that the fire was suspicious."

Classes were cancelled for the remainder of the day Thursday and Friday due to the damage and the ongoing investigation, the district said.

"We are working with the school board and the local fire department to establish how and why this occurred, and who was involved," said Cpl. Dave Starr of the North Cowichan/Duncan RCMP.

School officials say they are working closely with police in the investigation.

Information about the collection of personal belongings from the school will be sent out by the district, officials said.