At least five people were killed last night in a shooting on the Molson Coors brewery in the USA.
There were reports that up to seven people had been killed, including the gunman. However, there was no confirmation of the exact number.
"A wicked murderer opened fire at a Molson Coors brewing company plant," President Donald Trump said lat night.
"It's a terrible thing. A number of other people were wounded, some badly wounded," he added.
"What has happened is there was a horrific shooting that has occurred," Milwaukee mayor Tom Barrett said.
"We're urging all residents and people in this area to stay away from this area. They're continuing their sweep to make sure there is nothing more that's occurring.
"It's a horrible, horrible day for the employees. It's a very rough day for anyone who is close to this situation," he said.
Police said there was no longer an active threat but did not immediately release details about the gunman or how the shooting unfolded.
It occurred at a sprawling complex that includes a mix of corporate offices and brewing facilities.
At least 600 people work at the complex, which is widely known in the Milwaukee area.
James Boyles said his wife, Lasonya Ragdales, who works at Molson Coors, was texting from inside the facility during the shooting and said she was locked in a room with a bunch of co-workers.
Attorney General Josh Kaul called the shooting "gut-wrenching."
The brewery has a packaging centre that fills thousands of cans and bottles every minute and a distribution centre the size of five football fields.