At least four dead, up to 30 wounded after factory employee opens fire in US state of Kansas, according to county sheriff

At least four people were killed and up to 30 wounded when a former employee opened fire at a lawn mower factory in a small Kansas town, police said.

Harvey County Sheriff T. Walton said the number of victims could possibly rise to seven.

He said the gunman was among the dead.

"The shooter has been shot and killed. He's an Excel employee," Walton said. "Authorities killed him."

"This is just a horrible incident that happened here," he said.

"There's going to be a lot of sad people before this is all over."

Witnesses reported seeing the gunman first shoot a woman in the parking lot of Excel Industries before entering the assembly area of the factory and opening fire.

"We want to know what triggered this. We need to know the history of the shooter, and then we have to try to heal," Walton told local TV.

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