UPDATE: A Defense Department spokesperson tells CNN Pentagon correspondent Barbara Starr that Tuesday’s “active shooter” situation at Walter Reed National Military Medical Center in Maryland was an “exercise.” No deaths or injuries were reported. Read Breitbart News’ original report below.

An active shooter situation is unfolding at Walter Reed National Military Medical Center in Maryland, according to Rep. Dutch Ruppersberger (D-MD).

“I am currently at Walter Reed Medical in Bethesda where we’ve been told there is an active shooter. I am currently safe in a conference room w/ approx 40 others,” Ruppersberger tweeted.

I am currently at Walter Reed Medical in Bethesda where we've been told there is an active shooter. I am currently safe in a conference room w/ approx 40 others. — Dutch Ruppersberger (@Call_Me_Dutch) November 27, 2018

Montgomery County Police Department said officers were called to assist with the possible active shooter situation. The center is currently on lock down.

According to NBC, the Naval Support Activity in Bethesda found “no indication so far of an active shooter” at the center. Authorities have cleared the hospital’s basement and are currently sweeping the remaining areas of the building.

No deaths or injuries have been reported at this time.