MEMPHIS, Tenn. — An explosion and fire at a North Memphis chemical plant injured two people Tuesday afternoon.

The Memphis Fire Department responded around 3:30 Tuesday afternoon to the PMC Biogenix chemical plant on Pope Street near Warford in North Memphis. They found heavy fire and smoke that was visible for miles.

The fire was brought under control around 5:30 p.m.

A fire official said one person was taken to a hospital listed in critical condition after suffering from hand and face burns. The victim has since been downgraded to a stable condition. Three other employees were treated on the scene with minor injuries.

More than 100 firefighters battled the blaze. The fire department said the product, a type of fatty acid, was stable and there was no environmental concern.

The origin of the fire and total damage are both currently unknown.