BETHESDA, Md. (WJZ) — Changes are coming to the alert system at Walter Reed Medical Center after a mistake sent the nation’s largest military hospital into lockdown last month.

Congressman Dutch Ruppersberger (D-MD 2nd District), was inside the hospital when it locked down. He said he met with military leaders about the incident to make sure it doesn’t happen again.

Inside the hospital, patients and doctors alike spent an hour and a half hiding from a shooter that did not exist.

No Active Shooter Found At Walter Reed Military Medical Center After ‘False Alarm’

“We locked down everything. Cut off the lights. Made sure nobody was in the hallway,” A hospital employee said.

They also created makeshift barricades to block a shooter from entering their hiding spots.

“Meanwhile, we are in this room with a desk in front of the door thinking there’s an active gunman and we didn’t know what was going on,” Ruppersberger said.

Congressman Dutch Ruppersberger tweeted from his spot, “Locked into a conference room with 40 people, only to learn it was a false alarm,”

First, the U.S. Navy Twitter account labeled the incident as a drill. But 30 minutes later, Naval Support said it was not a drill.

The real explanation did not come until the end of the day.

A service member had accidentally triggered the emergency alert to more than 3,800 people, and that quick press of a button became a major scare.

The Navy has since said it will explore safeguards to its alert system.

Protocols Being Updated Following Walter Reed Lockdown

Ruppersberger said he is confident military officials are working to make sure this does not happen again unless the threat is real.

“They recommended better training, and that more people be involved in the process, and that they were going to follow through with the whole system and continue to evaluate,” Ruppersberger said.

He said the medical campus is working on improving how first responders are able to access buildings in the event of an emergency.

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