LYNN – Fire investigators in Peabody and Lynn had a busy night Sunday.A reported arson occurred outside Sullivan Tires on the Lynnway in Lynn shortly before 10 p.m. Sunday.A passerby called the fire department after watching a Dodge Durango truck burst into flames and a man running away, authorities said.A man who fit the description of the suspect was detained by police on Commercial Street a short time later, but was only arrested for outstanding warrants, police said.Another fire in Lynn was reported at about 11:30 p.m. at 91 Flint St.Fire Inspector Don Baron says a small fire broke out at the rear of a garage. He said the fire was small and contained to a rear wall causing minor damage.In Peabody, arson investigators converged on the parking lot of American Chimney Sweeps at 62 Pulaski St. for an attempted arson that was reported at 7:45 a.m. Monday.An employee reported that someone tried to light one of the company trucks, a 2006 GMC Savana, on fire overnight.Authorities are investigating the Peabody incident as arson, but provided few details Monday.All three incidents are still under investigation and official causes have not been released.