A chemical leak from a train car in Whitewater Township, near Cincinnati, prompted Ohio officials to issue evacuation orders on Tuesday due to concerns about a potential explosion. The big picture: Hamilton County,

Authorities in Hamilton County, Ohio, said the rail car was leaking styrene, a toxic and flammable chemical that is used to make plastic and rubber.

Hundreds of people returned to their homes Wednesday night after firefighters responded to a railyard for a reported chemical leak in Ohio.

A Train car in Hamilton County, Ohio had an open valve that leaked styrene and forced an emergency evacuation for anyone within a half mile radius of the area. (Credit: Aaron Vetter/Facebook)

An evacuation order remains in effect for residents in an Ohio community as crews work at the scene of a dangerous chemical leak

Residents near Cincinnati were urged to leave their homes due to the chemical leak as officials said there were concerns about a possible explosion.

Residents in an Ohio community where a dangerous chemical leak occurred have been allowed to return to their homes. An evacuation order was issued shortly after styrene, a toxic and flammable chemical that is used to make plastic and rubber,

The leak in Whitewater Township involves styrene, a gas used in producing plastic, rubber, fiberglass and other structural material.