Police said the fiery attack occurred at 3:10 a.m. on Dec. 1 on board a Harlem-bound 3 train traveling between the 34th Street-Penn Station and Times Square-42nd Street stops. Law enforcement sources said the unidentified perpetrator approached the dozing man, aged 55, and used an unidentified substance to set fire to the victim's lower body. The victim managed to exit the train at Times Square-42nd Street and seek assistance.