Three men were arrested in Mattapan Sunday night and have been charged with unlawful possession of a firearm and ammunition, resisting arrest, and assault and battery on a police officer, according to Boston police. Police stopped Daneroy Gordon, 29, of Hyde Park, Locksley Carroll, 24, of Hyde Park, and Maurice Sexton, 19, of Dorchester, as they walked along Blue Hill Avenue after residents in the area reported hearing gun shots around midnight, police said in a statement. While police frisked Carroll for a weapon, Gordon and Sexton attempted to flee in a car, police said. Police ordered them to stop. Officers said Gordon grabbed a firearm from his waistband. As police wrestled for the gun, it fell to the ground and police recovered it, they said. The men will be arraigned this morning.