HUNTINGTON, Long Island (WABC) -- Imagine going to rinse your hands and black sludge comes out of the faucet.
That's exactly what happened to a woman on an LIRR train and she recorded it with her phone to prove it.
Now the LIRR is investigating what went wrong.
The train was bound for Huntington from Penn Station Monday afternoon, and a passenger was using a train bathroom in one of the rear cars.
But she wishes she hadn't. "It was just like nasty, oxidated, like sludge stuff coming out of the faucet," said the passenger.
The question is, what was it? A spokesperson for the railroad told us they're not sure yet.
But they say the car in which it happened has been identified and pulled out of service.
They also encourage any passenger who spots something like this to call 511 and to write down the car number written on the wall at the end of each train car.
They say the problem most likely originated from the water supply at West Side Yard, where the entire system is now being flushed.
As for passengers, safe to say they were not surprised by the video, but: "Eww, that is so foul, that is horrifying," said one passenger.
"I wish I didn't touch it the first time," said the passenger who encountered the sludge. "Like I hope I don't mutate or anything."
Two words: hand sanitizer.
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LIRR investigating after black sludge pours out of faucet on train