An early morning fire in Lamoine is under investigation. Deputy Fire Chief Stu Marckoon says they received a call just before three Wednesday morning. He says the caller heard what sounded like gunshots and could not tell what was burning. When crews arrived on the Bay Road they found an RV and screened in deck fully engulfed in flames. Marckoon says no one was there at the time. The RV had just been hooked up to electricity. Crews from several towns helped put the fire out. The Fire Marshal's Office is investigating what started the fire.