AFFTON, Mo. (AP) — A firefighter was injured Thursday during a large fire at a chemical plant in eastern Missouri that forced evacuations in nearby neighborhoods.

Fire personnel responded to the scene at the Manor Chemical Plant in Affton, where the fire was reported about 2:45 p.m., authorities said. Witnesses in the area reported hearing several explosions during the fire.

Employees of the plant were evacuated safely and the fire was extinguished by about 5 p.m., said Lt. Matt Coppin of the Metro West Fire Protection District.

The firefighter was taken to a hospital but Coppin said he didn’t know the extent of the injuries or how the firefighter was injured.

The south St. Louis County business is a wholesale chemical distributor but also makes “custom blends” of chemicals for cars, paint, printing, dry cleaning and industrial manufacturing, according to its website. Some of the products Manor Chemicals sells include acetone, rubbing alcohol and other flammable chemicals.

Up to 10 chemicals may have been involved in the fire, Coppin said. Thirteen fire agencies and 62 fire trucks responded to the blaze.

St. Louis County police helped evacuate people within a half-mile of the plant. St. Louis County police said most residents and businesses were allowed to return about 6 p.m.

Students in Affton schools were held past dismissal until about 4:45 p.m., when school officials were allowed to release them.