Investigators were probing the possibility that an explosion at a West Hollywood apartment complex that wounded one person and displaced 12 others was the result of a drug cook that went bad.
The explosion was reported at 6:50 p.m. at 1260 Havenhurst Drive, between Santa Monica Boulevard and Fountain Avenue, according to the Los Angeles County Fire Department.
The person believed to have been cooking the marijuana suffered first- and second-degree burns and was taken to a hospital.
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Officials said the man was likely using a popular process known as "Honey Butter" or "Honey Oil" extraction.
"The person that was actually injured was in his apartment and he was using chemicals with marijuana to extract THC," said Inspector Quvondo Johnson, of the Los Angeles County Fire Department. "Whatever he was doing it had a flash and it blew out the window."
Resident Patrick Cunningham thought something was wrong with his microwave.
"I felt it before I heard it," he said. "I thought a boiler had blown."
The Honey Butter process is an extremely dangerous method of using a flammable accelerant to extract the hallucinogenic chemical tetrahydrocannabinols -- or THC -- contained in marijuana plants.
The method has resulted in several recent cases of explosions at homes.
Earlier this month, an explosion from a marijuana cook gone bad severely wounded three men and set a quiet Monrovia neighborhood on edge.
It was the second time in less than a week that police have responded to an explosion involving marijuana in the region.