The Concord Fire Marhsals Office is investigating after a massive overnight fire damaged two homes in Concord. Concord Fire said they received a call regarding large amounts of smoke coming from a home off of Elrond Drive just before 1 a.m. Saturday. Fire crews said when they arrived on scene, an "extensive" amount of fire could be seen coming from the home. Neighbors said they called 911 after they heard "cracking" and "popping." Officials said the neighbors who initially called 911 sustained damage to their home from the heat of the fire. Authorities said approximately 30 firefighters from the Concord and Odell Fire Departments battled the fire.