PORT ANGELES — A man allegedly trying to extract THC from marijuana in a shed on Liberty Street caused a fire that destroyed the building Saturday morning and prompted a detour off Front Street, Port Angeles police said.

It also may have caused an explosion reported by witnesses,

“We’re quite confident the cause [of the fire] was the extraction process,” Sgt. Glen Roggenbuck said. “Just exactly how that process started the fire and caused the explosion, we don’t know.”

The fire was reported at about 10:50 a.m. Saturday.

Authorities shut down both lanes of Front Street until about 1:30 p.m. so fire crews could stretch hoses across the road and connect them to hydrants.

Scott C. Lesure, 35, a resident of the home on the same property as the shed at 213 N. Liberty St., was taken to Olympic Medical Center for treatment of burns suffered in the fire.

Lesure had been treated and discharged as of 2:30 p.m. Saturday, according to a hospital nursing supervisor.

Roggenbuck said police intend to recommend that the Clallam County Prosecuting Attorney’s Office charge Lesure, who was not arrested Saturday, with reckless endangerment.

Crews from both the Port Angeles Fire Department and Clallam County Fire District No. 2 were called to the blaze, which sent a column of smoke billowing into the sky.

“[The shed] was totaled, there’s no question,” Port Angeles Fire Chief Ken Dubuc said, though a damage estimate was not immediately available.

“It did not look like it extended into the house.”

Roy Evans, who lives across Liberty Street from the fire, said he called 9-1-1 after he saw black smoke billowing out of a small chimney on the shed’s roof.

Evans said he also heard a “whoomph” sound like a small explosion inside the building as smoke spread to the end of the structure opposite the chimney.

Roggenbuck said a Lower Elwha Klallam tribal officer who happened to be driving by on Front Street reported hearing the 9-1-1 call come from emergency dispatchers and within 30 seconds heard an explosion and saw smoke as he turned off Front onto Race Street to respond to the fire.

“Obviously, there was quite an explosion, but I don’t know if we’ll ever know what exactly exploded,” Roggenbuck said, adding that police do know Lesure had a butane torch in the shed.

Roggenbuck said Lesure told police he was trying to extract THC — or tetrahydrocannabinol, the active ingredient in marijuana — for a friend who has permission to use medical marijuana.

“We will try to confirm that for certain,” Roggenbuck said.

A similar cause is suspected in an apartment fire in Kirkland that hospitalized two men and caused about $100,000 in damage last week, according to a Saturday story in The Seattle Times.

A common way of extracting THC is dosing dried marijuana with a solvent, such as butane, which strips the active chemical from the plant, according to the Times.

The butane is then burned off in some way, the Times said, which can lead to the butane vapor igniting and starting a fire.

________

Reporter Jeremy Schwartz can be reached at 360-452-2345, ext. 5074, or at jschwartz@peninsuladailynews.com.