The Edmonton Police Service’s arson unit is investigating a fire that ravaged a historical building in the city’s downtown Tuesday.

Melanie Mochoruk, a spokeswoman with Edmonton Fire Rescue Services, said police have confirmed the fire that caused $3.5 million in damages to the Ramsey Building was purposely set.

Roughly 60 firefighters were seen battling the blaze in the Ramsey Building on Rice Howard Way — a building that was built before the Great Depression.

Firefighters say the blaze originated in an abandoned area in the upper floor of the building, and its narrow hallways gave crews a hard time fighting the flames.