INSTITUTE -- One worker was killed and a second injured in an explosion at a chemical plant that shook an area west of Charleston.

The explosion, which sent a fireball hundreds of feet into the air and could be felt miles away, occurred about 10:25 p.m. Thursday. The blast occurred in a section of the Bayer CropScience plant where waste products are treated before disposal, Bayer spokesman Mike Wey said.

The unit had been closed for maintenance and was restarted earlier in the week, he said. A state official said the chemical that appears to be involved is not especially toxic.

A worker who had been counted as missing was killed in the explosion, Kanawha County Emergency Management Director Dale Petry said Friday. He did not have any other details.

Wey said the injured worker suffered burns and was transferred to a Pittsburgh hospital. A company emergency responder was treated at the plant infirmary for heat stress, Wey said.

An eight-person crew normally works the unit at the plant, Wey said. The other six workers were not injured, he said.

"Our thoughts and prayers are with the families of these employees during this very difficult time. We hope yours and the community follow as well," Bayer said in a statement issued Friday morning. "This is a very sad day for the Institute site family."

Bayer said the cause of explosion has not been determined. The unit was shut down and will not be restarted until the company determines that it can be safely operated.

Emergency crews extinguished the fire at about 2 a.m. Friday, Bayer said.

The plant is located about 10 miles west of Charleston. State Department of Environmental Protection spokeswoman Kathy Cosco said the plant produces several chemicals, including the one primarily involved in the fire, methyl isobutyl ketone.

Methyl isobutyl ketone is used a solvent for gums, resins, paints, varnishes, lacquers and nitrocellulose, according the U.S. Environmental Protection Agency's Web site.

Cosco said the chemical isn't particularly toxic but is highly flammable. Air monitoring found no sign of chemical exposure, either on or off the site, Bayer said.

Residents miles away from the facility reported hearing the explosion.

"I personally live about 10 miles from the plant and I felt it," said Kanawha County Manager Brent Pauley.

West Virginia State University Police Department patrolman Robert Flinn said he felt the explosion as he was sitting in his cruiser on the school's campus near the plant.

"Our back was turned, and it was like somebody shined a giant spotlight on us," he said.

Warne Ferguson lives less than a mile from the plant and the explosion shook his house.

"It scared my wife to death," said 81-year-old Ferguson. "I thought my house was falling down on top of me. That's how hard the vibration was."

As a precaution, emergency officials temporarily closed Interstate 64, U.S. 60 and state Route 25. Also, residents in at least five nearby communities were told to stay indoors. The highways were reopened and shelter-in-place orders lifted shortly after 2 a.m. Friday.



Copyright 2008 The Associated Press