A gunman opened fire Wednesday at the Molson Coors brewery in Milwaukee. “Multiple” people were killed, according to the mayor, including the shooter.

The gunman was said to be a recently fired brewery worker. One report indicated he took his own life.

“There are multiple people who have died, I believe including the shooter,” Milwaukee Mayor Tom Barrett said, shortly after the attack. “There was a horrific shooting that occurred… It is a horrible horrible day for the employees here.”

The Milwaukee Journal Sentinal initially put the death toll — including the gunman — at 7, citing “multiple” sources. Others were reported wounded.

Police did not confirm the number of dead, but if correct, it would tie the second-worst shooting in the city’s history; in 2005, 8 were killed at a church service, including the shooter, who committed suicide.

The Molson Coors brewery, along with businesses and schools near the shooting scene, went on lockdown as authorities urged people to stay away from the area. The school and most business lockdowns were lifted a few hours later.

Several law enforcement agencies, including the Bureau of Alcohol, Tobacco, Firearms, and Explosives joined the investigation.

“Gun violence has taken too many lives in Milwaukee and the mass shooting today is heartbreaking,” Sen. Tammy Baldwin (D-WI) wrote. “I want to thank the first responders who ran into harm’s way and saved lives.”

The attack occurred “at a sprawling complex that includes a mix of corporate offices and brewing facilities,” the Associated Press reported. At least 600 people work at the complex, which is widely known in the Milwaukee area as ‘Miller Valley,’ a reference to the Miller Brewing Co. that is now part of Molson Coors.

“’Miller Valley’ features a 160-year-old brewery, with a packaging center that fills thousands of cans and bottles every minute and a distribution center the size of five football fields. A massive red Miller sign towers over the complex and is a well-known symbol in Milwaukee, where beer and brewing are intertwined in the city’s history,” the AP said.

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