Cause of mosque fire labeled 'suspicious' - Houston Chronicle "They're not going to assume anything," said Ruy Lozano, spokesman with the Houston Fire Department, noting that the investigation is ongoing. While officials did find multiple points of origin, they can't be sure that indicates arson, saying that if a fire starts on the roof, for example, and drops debris, it can mimic patterns seen in arson cases, Lozano said. "As part of the investigative process, evidence is being collected and analyzed, and interviews are being conducted," the fire department said in a release Saturday. "We want to reassure the public that we will conduct a complete and thorough investigation."