FOREST GROVE, Ore. - Firefighters in Forest Grove believe an explosion and two-alarm fire that critically injured one man was caused by someone making hashish oil.
The fire started at a home near the Pacific University campus, at Main Street and 22nd Avenue around 4 a.m. Friday.
Crews said they found smoke billowing out of the house when they arrived.
The fire was completely out by 5:30 a.m. Firefighters said it was never a threat to surrounding homes.
Five people were inside the home during the explosion. One person escaped by jumping out of a second-floor window, firefighters said.
A man in his 20s was taken to a hospital with serious burns. He is in critical condition, according to Forest Grove police.
None of the others needed to go a hospital.
Firefighters said witnesses told them the explosion was caused by someone making hashish oil, which is concentrated marijuana. Its production can be a fire risk because it's prepared using butane.
Drug investigators were called to the scene. Their investigating was delayed when the fire started again in the home's attic.
No arrested have been made at this time.
The Red Cross is helping the five adults and one child who were displaced by the fire.
Friday's blast was the second involving hash oil in the last year in Forest Grove. In March 2013, five people were hurt in a hash oil cooking explosion. One man was arrested.
KATU's Stephen Mayer contributed to this story.