The Rhode Island Department of Environmental Management says an incident involving an officer firing his gun is being investigated. The DEM says the officer had been struck and injured by a man on a dirt bike in the Big River Management Area in West Greenwich at around 12:30 p.m. Saturday. Authorities say a Coventry man, Austin DiPeitro, was arrested on charges including assaulting a police officer. The officer involved was reportedly taken to Kent County Hospital by ambulance.