PORTLAND -- The bomb squad was called to small pipe bomb explosion in North Portland Monday morning, police said.
Police were called just before 9:30 a.m. to the the report of an explosion behind Tom's Pizza, at 2630 N Lombard Street, said Portland police Sgt. Pete Simpson.
"Officers arrived at the scene and located evidence of some kind of small explosion," Simpson said. "There are no injuries and property damage appears to be minor."
The Metropolitan Explosives Disposal Unit was investigating. Police have not mentioned a possible suspect or motive.