A large explosion rocked a chemistry school in eastern France on Friday, killing a professor and injuring another person, authorities said. About 10 people were unaccounted for.
Preliminary indications were that the explosion was not caused by a bomb or act of terrorism.
The blast occurred on the ground floor of the Superior National School of Chemistry in Mulhouse, near France's border with Germany, and was followed by a fire, officials said.
The surrounding area was evacuated, and firefighters put out the subsequent blaze.
Teachers were counting students to determine whether there were any other casualties, France-Info radio reported from the scene.
"We thought it was an earthquake," a resident identified as Jean-Pierre Langer told TF1 television. "It really shook."