WINSTON-SALEM (AP) — The city of Winston-Salem is asking people within one mile of a blaze at a fertilizer plant to evacuate due to the possibility of a large explosion.

WGHP-TV reports that the fire started Monday night at the Weaver Fertilizer Plant on North Cherry Street. City officials have confirmed small explosions at the plant.

Firefighters say there is the potential for a large explosion of ammonium nitrate. Winston-Salem Fire Chief Trey Mayo says fire crews “abandoned” the fire-fighting operation because of the large volume of ammonium nitrate on site.

Firefighters could not flow enough volume of water to be reasonably certain that they could keep it cool enough to prevent a detonation.

“Don’t wait for something to happen. Something has happened. Now is the time to get out,” Mayo said on Twitter.

The building has collapsed as well, and access to the product that is in the building is restricted.

According to a Winston-Salem Police Department news release, the 4400 block of Cherry Street from North Point Boulevard to Indiana Avenue was closed while emergency crews responded to the fire around 8:20 p.m. and remains closed.

Wake Forest University released a statement asking some students in off-campus housing to voluntarily evacuate.

People who have evacuated should plan to be away from their homes for up to 48 hours.