An apparently homeless man turned a subway car into his personal No. 1 train.
Cell phone video shows the man laid out on a subway bench casually unleashing a river of urine on the floor of a 4 or 5 train — and the MTA has referred the revolting episode to police.
The footage, provided to the Daily News by a source, captures the moment the subway ride really went into the toilet thanks to the half-asleep man, who began relieving himself without opening his eyes while a group of grossed-out straphangers standing nearby tried to ignore him.
A large plastic garbage bag sits on the floor next to him, and someone can be heard laughing off-screen.