The Independent CANAL FULTON Investigators say materials used in the making of butane hash oil may have sparked the explosion that rocked an apartment complex Thursday evening. Canal Fulton police along with the Ohio Bureau of Criminal Investigation and the Ohio State Fire Marshal executed a search warrant Friday afternoon on an apartment occupied by a 25-year-old man. They found "a lot" of materials associated with the manufacturing of shatter, a high potency THC for vaping, Police Chief Doug Swartz said. The substance is very volatile, he said. Investigators continue to search for how the substance exploded. Swartz said there are other cases in Northeast Ohio where a dryer and a freezer ignited the shatter.