In fact, we just learned from the mayor of Milwaukee that there are multiple people dead, including the shooter, the first word of an active shooter at the Molson Coors campus in Milwaukee today, hundreds of officers, including the FBI, responding a massive show of force, their officers climbing to the roof, the neighborhood on lock down.

Sources say that shooter was disgruntled.

A former employee, in fact.

And here's our chief justice correspondent, Pierre Thomas, with late reporting shots ringing out at the Molson Coors sprawling beer plant in Milwaukee.

Roughly 2 p.m. Some 600 workers order to shelter in place as an army of police respond.

Television helicopters capturing it all.

You can see there's a handful of officers now with their rifles.

They just came out of this stairwell year and a rooftop door.

They're going into another one.

There are reports of injured.

You can hear sirens in the background, so we still have even Maur first responders heading this way.

Neighboring schools placed on lock down worried families rushing to the scene.

I was afraid for my dear life with my baby.

This remains an active scene police tonight, saying the shooter fatally shot five people before apparently killing himself with a self inflicted gunshot wound.

Described by sources as a disgruntled employee.

The victims all worked at Molson course, and no members of the general public were involved.

Let's get to Pierre Thomas with this live tonight and Pierre, we're aware that the FBI is already on the scene.

That's right, David.

The FBI is assisting a T F.

Is there as well, all hands on deck with such a large crime scene.

One source telling us it may be hours before the complex is completely cleared.

David will stay on it.

Pierre, Thank you.

Hi, everyone.

George Stephanopoulos here.

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