Investigators with Portland Fire & Rescue say they have reason to believe the fire that sent up a dark plume of smoke visible citywide Monday evening was human-caused. But officials are refraining from calling it arson, as they try to better understand the circumstances surrounding the blaze.

“If this is human set, but an accident and a careless one, that’s one thing,” said Rich Chatman, a spokesperson for the department. “But if it’s human set [by] someone who intended to actually harm those houses that were, and the business that was and the field that was, then we’ve got a different situation.” 

The bureau believes the fire began in an old overgrown driving range in Northeast Portland. Wind carried the flames south toward NE 84th Street, where it damaged five town houses and three businesses, including the Grand Avenue Boxing Club, according to Chatman. Two of the structures were destroyed beyond repair. More than 10,000 homes and businesses temporarily lost power.

The department’s remaining tight-lipped as to why it believes the blaze was human-caused. Chatman said officials are hoping for people to come forward with information that could confirm their understanding of what transpired, and don’t want to taint the tip pool. 

The department is asking people to report any information about the fire’s origin to their tip line at 503-823-INFO.