A 23-year-old New York man is in custody after a 28-hour stabbing spree during which he allegedly murdered his stepfather, his ex-girlfriend, and her mother. Police said he also fatally hit a pedestrian while driving a stolen Lexus. Around 5 a.m. Friday, authorities say, Maksim Gelman stabbed his stepfather to death at their home in Brooklyn's Sheepshead Bay. Several hours later, he entered the apartment his former girlfriend shared with her mother, and fatally stabbed the older woman at least a dozen times. Later that afternoon, when his girlfriend returned home, she too was stabbed to death. On Saturday morning, police said he ended his rampage by stabbing a man aboard a subway car near Manhattan’s Times Square.