MILWAUKEE (AP) — Milwaukee Mayor Tom Barrett says multiple people have been killed in a shooting on the Molson Coors Brewing Co. campus. Barrett did not give an exact number of people killed in Wednesday’s shooting. He called it “a horrible, horrible day for the employees here.”

WISN-TV in Milwaukee reported Wednesday that a Molson Coors employee received an email about an active shooter near one of the buildings.

Company spokesman Martin Maloney said there was an “active situation” but didn’t have any further details. There was a heavy police presence in the area, along with fire trucks and ambulances.

Milwaukee police asked that people stay clear of the area and that no helicopters or drones be flown over the site for “officer safety purposes.”