Four people were wounded during a shooting incident at a software company in a suburb of Madison, Wisconsin, according to a city administrator.
The suspected shooter was also critically injured during the late-morning attack at WTS Paradigm in Middleton, City Administrator Mike Davis said.
He said police have lifted a lockdown, but did not immediately have additional information.
A spokeswoman at University Hospital said the hospital has accepted four patients from the shooting.
Their conditions were not immediately available.
Judy Lahmers, a business analyst at WTS Paradigm, said she was working at her desk when she heard shots at about 10am. She said it sounded “like somebody was dropping boards on the ground, really loud”.
Ms Lahmers said she ran out of the building and hid behind a car. She said the building’s glass entrance door shattered.
“I’m not looking back, I’m running as fast as I can. You just wonder, ‘Do you hide or do you run?’” she said.
She said she knew that one co-worker had been grazed by a shot but was OK. She did not have any other information. She said the shooting was “totally unexpected. We’re all software people. We have a good group”.
The State Journal newspaper reports that one woman was taken out of the building screaming, saying it was “a devastating loss” and being held up by another person.
Gabe Geib, a customer advocate at Esker Software, said he was working at his desk when he heard a couple of shots coming from next door which “sounded like claps”.
He said he then saw people running “full sprint” away from the building.
“We knew at that point that something was going down. A ton of people were running across the street right in front of us,” he said.
More than an hour after the shooting, he and his colleagues were huddled in place in their cafeteria, away from windows.
Jeff Greene, who also works at Esker, said police told those gathered in the cafeteria to go a nearby hotel to make a statement about what they saw.
At least 40 people were gathered in the hotel’s car park, waiting to be interviewed by police.