Detectives from the Los Angeles Police Department’s major crimes division were working with the city Fire Department’s arson investigators to determine what might have sparked the blast that shot a ball of flames out of the building Saturday night and scorched a fire truck across the street, police spokesman Josh Rubenstein said.
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Three firefighters were released after spending the night in the hospital, fire department spokesman Nicholas Prange said Sunday. Of the eight who remained hospitalized, two were in critical but stable condition, he said. Officials initially announced that 11 firefighters were injured. But Prange said a 12th was treated and released for a minor injury.

Erik Scott, a spokesman for LAFD, later told KTLA two firefighters who were on ventilators were taken off the devices. “They continue to remain in the intensive care unit for treatment of significant burn injuries,” the department said of the pair.
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Scott said the building was a warehouse for SmokeTokes, which he described as a supplier for makers of “butane honey oil.” Butane is an odorless gas that easily ignites, and it’s used in the process to extract the high-inducing chemical THC from cannabis to create a highly potent concentrate also known as hash oil. The oil is used in vape pens, edibles, waxes and other products.
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In 2016, there was another major fire at a business called Smoke Tokes at a nearby address. The Los Angeles Times reported at the time that it took more than 160 firefighters to put out the blaze and that they encountered pressurized gas cylinders that exploded in the fire.
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