Fire officials are warning the public about the dangers of smoking following a mattress fire in Chatham. The fire was quickly extinguished and damage was confined to the mattress. The building’s maintenance staff helped the tenant get out of the building safely before firefighters arrived and no injuries were reported. Fire officials said the fire was accidently caused by a lit cigarette. “Smoking materials continue to be a leading cause of fatal home fires,” said Whitney Burk, the fire department’s public information officer.