On Thursday morning, the Waldo County Emergency Agency and the city of Belfast issued an alert regarding a fire that broke out at the Penobscot McCrum potato processing plant, located on Pierce Street.

“The Fire Department and Police Department are responding to the fire. Waldo County Emergency Management Agency advises that Belfast residents shelter in place until otherwise notified,” the alert said.

At around 9:30 a.m. ET, a spokesperson for the Belfast Fire Department told Newsweek that fire crews were still on scene working to extinguish the fire. No information on the cause or size of the fire was immediately available, the spokesperson said.

According to the Bangor Daily News, Belfast Mayor Eric Sanders was at the scene of the fire on Thursday morning and said that the city’s main concern is the fact that ammonia tanks are located on the potato plant’s property.

“These people mean a lot to me, so. They’re good people, and they’ve been battling it since what, 2 a.m.. So I think the best thing we novices can do right now is stay the hell out of the way and pray to God the tanks don’t blow,” Sanders said, according to the Bangor Daily News.

On Facebook, the Belfast Area High Schools information page announced that the school will be closed today due to the fire. “Let’s keep the employees and firefighters in our hearts. We will send updates as available,” the school said in the post.

While it was unclear what caused the fire, several photos and videos posted on social media showed clouds of smoke traveling into the sky throughout the city.

“At the Shell gas station in Belfast, 1.5 miles from Penobscot McCrum. Smoke still moving strong nearby,” Twitter user Dave Dyer wrote in a tweet showing clouds of smoke from the fire.

Adam Bartow of Portland, Maine’s WMTW-TV shared a picture of fire crews working to extinguish the fire.

“#BreakingNews a huge fire is burning at the Penobscot McCrum potato processing plant in Belfast, Maine. Crews from multiple towns are on scene,” Bartow wrote.

While speaking with the Bangor Daily News, Jay McCrum, the owner of the potato processing plant, said that around seven employees were working in the facility when the fire broke out but they were all able to safely evacuate.

“I’m doing good because everybody is safe,” McCrum said, according to the Bangor Daily News. “And all the fire departments have been phenomenal.”

Newsweek reached out to the city of Belfast for updated information but did not receive a response in time for publication.