Law enforcement sources identified the gunman to ABC News.

Law enforcement officials identified 51-year-old Anthony Ferrill as the employee of the Molson Coors Beverage Company who gunned down five co-workers at the company’s Milwaukee brewery campus.

Ferrill left the MillerCoors campus and returned to the site with a gun on Wednesday, opening fire around 2 p.m. local time, law enforcement officials briefed on the probe told ABC News.

The victims were identified by Milwaukee Police Chief Alfonso Morales as employees Jesus Valle Jr., 33; Gennady Levshetz, 61; Trevor Wetselaar, 33; Dana Walk, 57; and Dale Hudson, 60.

The employees were powerhouse operators, machinists and electricians, Molson Coors CEO Gavin Hattersley told reporters during a press conference Thursday.

“But more importantly, they were husbands, they were fathers, and they were friends,” Hattersley said.

No other victims were injured in Wednesday afternoon’s mass shooting, Milwaukee police said. Ferrill, a resident of Milwaukee, died from an apparent self-inflicted gunshot wound, police said.

The attack garnered a massive response of first responders to the brewery.

Investigators do not yet know the motive of the shooting or how the incident transpired, Morales said.

Milwaukee Mayor Tom Barrett described Molson Coors as the “fabric of this community” for more than a century and a half and emphasized the need for support in the aftermath of the shooting.

“We should also recognize that they are going to need our help as a community, because they’ve gone through something that no one ever wants to go through — a sudden, tragic, unexpected, unbelievable loss of life,” he said.

Hattersley said Wednesday in response to the shooting, “There are no words to express the deep sadness many of us are feeling right now.”

Wisconsin Gov. Tony Evers said in a statement, “Our hearts go out to the families of those whose lives were senselessly taken, all of the folks and workers at Molson Coors, and the Milwaukee community as we grapple with yet another act of gun violence that will have long-lasting consequences for this community and our state.”