Worker goes on killing spree at US factory

Several hours later, police were still inside Swiss-based ABB Group's plant, going room to room in a search for both the gunman and

additional victims, police Captain Sam Dotson said. Authorities had not confirmed whether the gunman was among the eight.

Fire Department spokesman Bob Keuss identified the suspected killer as Timothy Hendron of Webster Groves, a St Louis suburb. Captain Dotson said Hendron was an employee of the plant.

The shooting occurred as a federal lawsuit Hendron and other ABB workers filed against the company in 2006 over their retirement plan was unfolding in a federal courtroom in Kansas City, Missouri. Court documents show that a bench trial began on Tuesday.

The lawsuit seeks to recover financial losses by the workers' retirement plan, claiming that ABB and its pension-review committee caused the plan to include investment options with "unreasonable and excessive" fees and expenses.

Gunfire broke out at about 6.30am during a shift change, and 40 to 50 people were thought to be in the factory at the time, Captain Dotson said. Employees scurried for safety.

"Many of them sought safety on the roof, in boilers and broom closets," Captain Dotson said.

Police said three of the injured were in critical condition and two were in fair condition.

Those seeking refuge on the roof faced bitter cold. The wind chill in St Louis dipped below zero.

Thomas Schmidt, an ABB corporate spokesman in Zurich, Switzerland, said in a statement: "This is obviously a very serious situation. The welfare of our employees is of utmost importance to us."