NASHVILLE (AP) — Officials are investigating a release of toxic ammonia gas at a Middle Tennessee chicken processing plant that led to the evacuation of more than 200 residents.

Fire officials said the gas leak at a Tyson Foods facility in Goodlettsville early Sunday was found by an overnight worker who alerted others at the industrial complex near the intersection of U.S. Highway 41 and Interstate 65, The Tennessean reported.

The leak was stopped by firefighters and plant officials by 8:15 a.m., officials said. Ammonia is used in the plant's refrigeration system.

About 240 residents and 20 workers were temporarily evacuated from the area while hazardous materials officials and plant managers investigated, Goodlettsville Fire Chief Kenneth Reeves said. One worker was assessed for injuries but no one was hospitalized, Reeves said.

Fire and police departments from Nashville and Goodlettsville responded to the incident. An investigation was ongoing.