A gunman has killed three people and wounded 14 others at his manufacturing workplace in central Kansas.
The shooting spree spanned several kilometres and ended when a lone police officer killed the suspect, authorities said.
While many of his victims were fellow workers, overall the attacker appears to have opened fire at random, said Harvey County Sheriff T. Walton of the mass killing that struck fear in Hesston and the town's major employer, a lawnmower manufacturing company.
"This is a horrible situation my friends, just terrible," Walton said at a news conference, adding at least five of the 14 wounded were in critical condition.
Some of the shooter's motives had emerged, but the sheriff declined to provide more details except to say the attack was "not terrorism".
"There were some things that triggered this particular individual," he said.
The Kansas shootings come after a Michigan man who worked as a driver for car-hailing service Uber was charged with killing six people during a shooting rampage last weekend.
In December, a husband and wife shot to death 14 people at a workplace holiday party in San Bernardino, California. The couple, who died in a shootout with police, were inspired by the militant group Islamic State, FBI officials said.
A number of mass shootings in the United States have elevated gun control as a campaign issue in the November US presidential election.
The Kansas attacker, who was armed with a .223-calibre assault-style rifle and a pistol, was driving a car when he began his attack about 14km southeast of Hesston in the town of Newton, where he shot a man in a truck, Walton said.
He then drove to a nearby intersection and shot another driver in the leg, before stealing that victim's car and driving over to Excel Industries, his work site, where he shot a person in the parking area, Walton said.
The gunman entered the plant, where he had been scheduled to work and where over 100 employees were beginning the day's second shift, and he opened fire on his co-workers, killing three, the sheriff said. Other employees fled in panic.
The first responding officer traded fire with the gunman near the building's paint room, striking him dead, Walton said.
"Even though (the officer) took fire, he went inside of that place and saved multiple, multiple lives - a hero, as far as I'm concerned," the sheriff said.
The gunman was killed 26 minutes after the first shooting was reported in Newton.
A dispatcher with the Sheriff's Department had identified the shooter as 38-year-old Cedric Ford and local television stations also reported that was the shooter's name, citing witnesses.
But Walton declined to identify the suspect, saying his identity would likely be released on Friday.
Meanwhile, police were positioned outside of the suspect's home in a tense stand-off with his room mate, who refused to allow them to enter to investigate, the sheriff said.
