GEISMAR, La. — State police say at least one person was killed and at least 30 were injured in an explosion and fire at a chemical plant in Louisiana.

State police Capt. Doug Cain said a hazardous material crew going through the plant in Geismar after the Thursday morning explosion found one person dead.

The cause of the blast, reported around 8:30 a.m., was not immediately known. The fire was out by late morning.

Eight of the injured were taken to Baton Rouge Medical Center, where one was listed in critical condition and two others were in serious condition.

Early tests did not indicate dangerous levels of any chemicals around the plant, about 20 miles southeast of Baton Rouge.