Updated 6:47 p.m. ET

Police are on the scene at the Molson Coors Brewing Company in Milwaukee after officials say a gunman opened fire on the campus Wednesday afternoon. Local officials say there are multiple fatalities, but did not give a definitive figure.

"This remains an active scene," Milwaukee Mayor Tom Barrett said at a late afternoon news conference. "There are multiple fatalities. We know that. The police department, the fire department have been working extensively. The sheriff is here as well."

The mayor called the incident "horrific," adding that he believes the gunman is among the dead. Barrett said law enforcement officials were sweeping the area to make sure "nothing more is occurring."

Later, the Milwaukee Police Department tweeted: "There is no active threat; however, this scene is still an active [one]."

Speaking at a White House news conference on the Trump administration's response to the new coronavirus, the president offered his "deepest condolences" to the families of shooting the victims.

"Earlier today a wicked murderer opened fire at a Molson Coors Brewing Company plant," he said, adding that several lives were lost and "a number of people were wounded, some badly wounded."

"Our hearts break for them and their loved ones. We send our condolences. We'll be with them," Trump said.

According to the Milwaukee Journal Sentinel, employees at the brewery complex received an email alert saying "an active shooter was in or near the second-floor stairwell" of Building 4 of the company's factory.

The paper notes that nearby schools were locked down, causing heightened anxiety for parents looking to pick their children up, awaiting an "all-clear."

Earlier, the Milwaukee police department tweeted that it was investigating "a critical incident" and urged residents to "stay clear of the area at this time."

Milwaukee television station WISN-12, an ABC affiliate, is reporting that the suspected shooter is a former Molson Coors employee. NPR has not independently verified that information.

Molson Coors, which brews Coors Light, Miller Light, Blue Moon Belgian White and others, changed its name from MillerCoors last year. USA Today reported in October that hundreds of corporate jobs were being moved to Milwaukee resulting in the loss of "400 to 500 employees" throughout the company.

This is a developing story and will be updated when more information becomes available.

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