A man suspected of gunning down three Bridgeport residents is in police custody Thursday.Police say Richard Roszkowski, 41, was arrested in Trumbull. Roszkowski is accused of shooting a man and women -- both in their 30s -- and a 12-year-old girl. The suspect and the three victims all knew each other, according to police. One theory police say they are following is the possibility that Roszkowski may have gone on a jealous rampage after being rejected by the woman for a new boyfriend.The three victims were shot on Seaview Avenue. The adults were pronounced dead at the scene. The girl was rushed to Bridgeport Hospital where she later died.