Washington, Feb 2 (IANS): A fire at a fertiliser plant in Winston-Salem, southeastern US state of North Carolina, forced thousands of people to evacuate.

The blaze reportedly started at the plant on Monday evening and was still active as of Tuesday morning.

At least 6,000 residents within a one-mile (1.6 kms) radius of the Weaver Fertilizer Plant have been mandated to leave their homes over the potential of an ammonium nitrate explosion. Nearby Wake Forest University cancelled classes for Tuesday, Xinhua news agency reported.

There were about 600 tons of ammonium nitrate, a chemical compound used widely in fertilisers and explosives, at the scene of the fire, according to officials.

Dozens of firefighters and up to about 150 emergency personnel have been working on the fire and evacuating the area.

Governor of North Carolina Roy Cooper tweeted on Tuesday that his office is in communication with state emergency agencies and local officials "regarding the dangerous fire in Winston-Salem."

"I appreciate the work of fireighters and the state will continue to provide any assistance necessary to get this fire under control," Cooper added.

With a population of roughly 250,000, Winston-Salem is in the northwestern part of North Carolina.