An active shooter scare at an Alpharetta business sent employees under desks, triggered a massive police response and prompted an evacuation Tuesday morning.

While a sweep of Fiserv ultimately found no threat and the evacuation order was lifted, the episode left employees shaken.

On Twitter, some reported hiding in closets and cramming in restrooms until officers arrived to escort them out of the building in the 2900 block of Westside Parkway.

“Everyone takes something like this very seriously,” a company spokeswoman told AJC.com. “And the important thing is that we confirmed there was no threat and ... the safety and security of our people is our top priority.”

Authorities learned of a “possible armed person” just before 10 a.m., when an alarm went off inside the building warning of an active shooter, according to Channel 2 Action News.

Police cars lined the Fiserv parking lot as officers blanketed the campus. As officers went through each floor of the business to ensure it was safe, some employees outside could be seen huddled in prayer.

The Alpharetta Department of Public Safety gave the all-clear just before 11 a.m. No gunman was found.

“We have no reason to believe there is a dangerous armed person on the loose in our community,” the department said.

Police are still investigating how the alarm was activated.

Fiserv is one of the nation’s biggest financial technology companies. Officials announced in January the company was acquiring First Data in Sandy Springs in a $22-billion merger expected to create a behemoth in the world of payments processing.

Alpharetta police officers checked each floor of the Fiserv building after someone reported an armed person in the area. No gunman was found.

Credit: JOHN SPINK / JOHN.SPINK@AJC.COM

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Credit: JOHN SPINK / JOHN.SPINK@AJC.COM

Fiserv is based in Wisconsin, but has significant operations in Alpharetta.

RELATED: Fiserv to buy metro Atlanta's First Data in $22B deal

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