YOUNGSTOWN, Ohio - Crews are working to stabilize a massive sinkhole in Youngstown.

The sinkhole opened up Sunday morning at the end of Shady Run Road on the city's south side.

The hole appears to be about 15 feet in diameter and at least 20 feet deep.

"It's slag and it's very unstable ground. And the shore is running underneath it so the water keeps moving the dirt away and there's no way to stabilize it until they drive some piles down to hold it steady," said Captain Ron Russo from the Youngstown Fire Department.

The water that caused the sinkhole also broke a gas line. Dominion East Ohio Gas shut off gas to three homes on the street while crews worked to repair the broken line.