A homeless man found on fire at Penn Station may be the victim of an arsonist who set him ablaze, police sources said Saturday. The 67-year-old victim was seen on fire at the bustling Midtown transit hub near W. 34th St. around 8:10 p.m. Friday by a commuter who alerted two MTA police officers. The victim was found near the entrance to the 1/2/3 train lines, suffering from severe burns to his legs and upper body, cops said. EMS rushed him to Weill Cornell Medical Center where he remained in critical condition on Saturday. Detectives are investigating the possibility that the homeless man was the victim of a criminal act, said a police source with knowledge of the case. Law enforcement was reviewing station surveillance footage and speaking to witnesses to see if anyone was seen near the homeless man before the fire broke out. No arrests have been made. The Penn Station incident comes fast on the heels of Sunday’s tragedy that shocked the nation, when a woman died after a man set her clothes on fire while she was sleeping aboard a subway car at the Coney Island-Stillwell Ave. station in Brooklyn, then callously fanned the flames with a shirt, according to police. Cops arrested Sebastian Zapeta, a Guatemalan migrant who had been living in a Brooklyn men’s shelter.