Police say an employee went on a rampage, killing at least five co workers before taking his own life.

Alex Perez is in Milwaukee this morning, Alex.

Good morning.

Hey, good morning.

Time for the more than 1000 people who work here Yesterday started out pretty normally until about two o'clock in the afternoon, when suddenly everyone's worst nightmare became a reality.

This morning, a tragedy at a Milwaukee landmark.

Never seen you like this.

Police say an employee opened fire at the old Miller Brewing headquarters, now the Molson Coors Company, killing five co workers before turning the gun on himself.

Investigators say the former employees returned to the office armed, opening fire on staff members.

Employees were evacuated along with neighboring schools as police searched more than 20 buildings on the company's campus.

I'm just glad I was able to get here in time, get him out of here and get him home.

All of us were just kind of in shock because we didn't know what's going on this worker says he walked away from the gunman to talk to someone else just seconds before the shooter pulled out the gun.

If I wouldn't have gone to talk to this guy who has relieved me, I'd be one of them guys.

I know that for a fact, because I would have walked right in what was going on.

More than 1000 people were working at the sprawling beer plant Wednesday afternoon when the shooting occurred.

This Miller Brewing site has been part of the Miller family and part of the city of Milwaukee for 165 years, and this is the saddest state do we have had?

And authorities at this point have not released any other details on the 51 year old gunman or his employment history.

This community now coming together to mourn those that were killed Robin, we're certainly thinking of everyone there.

Alex.

Thank you.

Hi, everyone.

George Stephanopoulos here.

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