Penticton RCMP say the Green Avenue fire is considered suspicious and is now being investigated as arson.
Police say investigators were delayed in accessing the site after workers and nearby residents were evacuated because of major safety hazards.
The scene was deemed safe to enter on Wednesday.
That allowed specialized fire investigators from the RCMP and Penticton Fire Department to complete their examination of the scene.
RCMP say they are conducting a criminal investigation and exploring every possible avenue to gather evidence, determine the cause of the fire and identify those responsible.
“The Penticton RCMP wants to acknowledge the amazing response from our frontline officers along with the Penticton Fire Department, Emergency Support Services, and all other agencies who responded to assist with tactical evacuations and fire suppression efforts,” said Supt. Beth McAndie, Penticton RCMP detachment commander.
“The assessment of this scene was unique, and it took several days to get the approval required to conduct the forensic fire examination.
“We appreciate the patience of the evacuees and those impacted by this incident. This investigation is a priority for the detachment.”
Police say the investigation remains in its early stages and no further details are being released at this time.
RCMP say relevant updates will be provided to the public when possible.
