PORTLAND, Ore. (AP) — Authorities say a fire that killed two men in North Portland was caused by a hash oil explosion.

Portland Fire & Rescue says 42-year-old Matthew McCrann died at the hospital after Monday's fire and the body of a second victim, 68-year-old Richard Cisler, was found in the debris.

Hashish oil is concentrated marijuana, and its production can be a fire risk because it's prepared using butane.

Cisler's brother, Earl, told KOIN-TV that his brother was working at McCrann's home on a remodeling project.