At least five people were killed in a shooting at the Molson Coors Brewing Company campus in Milwaukee, Wisconsin, local media report.
The gunman was also killed. The motive for the attack remains unclear.
The shooting occurred in the early afternoon while hundreds of employees were still at work. Molson Coors owns the Coors and Miller beer brands.
Local police, the FBI and federal firearms agents were also responding to the attack.
Nearby schools and businesses were locked down as the incident unfolded, local media say.
The company and police have not provided additional details on what is still an active situation.
Wisconsin congressman Mike Gallagher condemned the attack on Twitter, saying: “There’s no place for these kinds of hateful and disgusting acts in our society.”
This is a breaking news story – more to follow.