Conde Nast Issues False 'Active Shooter' Alarm in Building

"WOAH everyone all at once got an automated message apologizing for the false alert of a shooter at the 3rd Ave Conde Nast offices," tweeted one freelancer just minutes ago. Woops? The (very) alarming company email chain is below.

The first email:

Received at 3:34pm

We have received reports that a firearm has been discharged on the 10th floor of 750 building, 3rd Avenue in New York. If you are in a safe location, remain where you are. Get behind a locked door, or hide behind some type of obstruction. Lay down on the floor, and remain as quite as possible. Evacuate the facility only if you deem this safe or necessary.

Followed only minutes later by:

Conde Nast Security Operation Center apologizes for a message received initially of reports of an active shooter at 750 3rd avenue. The message was sent in error. It was a department drill. Please accept our apologies. Please disregard.