JACKSON (AP) — An explosion Saturday at the International Paper mill in Redwood killed a contract worker and sent 17 other contractors to a hospital, according to a statement from a company spokeswoman.

“We have accounted for all IP employees, and no employees were hurt. An investigation will be conducted to determine the cause of the accident,” a statement from Amy J. Sawyer said.

Her statement said the explosion occurred as the mill’s recovery boiler was being started after the annual maintenance shutdown for the mill in Redwood, about 32 miles from Jackson.

Warren County coroner Doug Huskey told the Associated Press late Saturday night that the victim was 28-year-old Marcus Christopher Broome of Bolton.

“He died of trauma to the chest and an autopsy will be performed Sunday at the state crime lab in Jackson,” Huskey said.

Hazel Hill, nurse supervisor at River Region Medical Center in Vicksburg, said five of the injured were being transferred late Saturday night to the Joseph M. Still Burn Center in Augusta.

When asked about by The Associated Press why they were being transferred, she said: “We are not a burn center.”

Hill said the others were treated and that “no patients had been admitted.”

The Warren County Sheriff’s Department, Vicksburg Fire Department, and IP security responded to the explosion.

IP said no damage estimates were available, and it would investigate the accident’s cause. The statement said the mill had not had any employee injuries in more than a year.

“The recovery boiler area, its processes and equipment are the most rigorously documented and monitored of any in the mill,” it said.

The company says it notified all appropriate state and federal safety and regulatory authorities.

John Adams, manager of environment health and safety at the Redwood mill, said at least 400 employees including contractors were on site when the explosion happened. He said officials with the Occupational Safety and Health Administration had arrived to investigate.

“OSHA talked to one of the contract site managers. They took a look at the periphery of where the boiler is located because we can’t get into the area proper because it’s not safe yet,” Adams said.

He said the explosion loosened some siding in the recovery boiler building — one of six to eight structures at the plant — but the building was still standing.

“We’re still trying to get to the bottom of the details and we have to secure the boiler. We have to make sure that the floors in the recovery boiler area are safe and that there won’t be any exposure for the people in that area,” Adams said.