Police and fire officials are at Kilborn Place, which also houses the Saskatoon Provincial Court House, and is the scene of the explosion.
“Investigators are dealing with what they believe is the detonation of an improvised explosive device,” the Saskatoon Police Service said in a statement.
“There are reports of some minor damage to the exterior of the building. There are no injuries.”
An explosives disposal unit is at the scene as well as a bomb detection K9 team, police said. No arrests have been made.