HOUSTON (CBSDFW.COM/CNN) – When a Molson Coors employee stormed the campus in Milwaukee and shot five co-workers the CEO of the company, Gavin Hattersley, was in Texas.

The Molson Coors’ annual conference was underway in Houston when Hattersley suddenly announced he was leaving.

News of the mass shooting came as hundreds were at the George R. Brown Convention Center, attending the three-day conference that began the day before. A reception that was planned after the conference was canceled and the event cut short after the news out of Wisconsin.

Molson Coors CEO Gavin Hattersley. (credit: molsoncoors.com)

Hattersley addressed the attendees, alerting them of the shooting, before reportedly flying back to Milwaukee.

The company did not identify the 51-year-old shooter who took his own life, but said he was an “active” employee at the facility. It did not provide details on a possible motive for the shooting Wednesday or the identities of the victims, pending family notification.

Police said all the people killed are Molson Coors employees, and were found in the same building.

More than 1,000 people were working at the campus when police received reports of a shooting just after 2:00 p.m. The complex includes a mix of corporate offices and brewing facilities — more than 20 buildings in all.

Emergency personnel work the scene of a shooting at the Molson Coors Brewing Co. campus on February 26, 2020 in Milwaukee, Wisconsin. (credit: Nuccio DiNuzzo/Getty Images)

Employees received texts and emails from the company warning them about the gunman.

“Active shooter, find a safe place, active shooter on campus. Reply with YES to confirm receipt,” the first text read.

“Active shooter We are still on lockdown, please remain in a safe place, police are investigating. Reply with YES to confirm receipt,” another one said.

Company officials say corporate offices will be closed for the rest of the week and the breweries will remain closed until further notice.

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