BETHESDA, Md. -- Panic surrounded Walter Reed National Military Medical Center after conflicting reports of an active shooter.

Reports of an active shooter at the hospital were unfounded and the U.S. Navy said the active shooter alert system was improperly activated ahead of a planned drill.

Walter Reed Bethesda tweeted that they were “secure from the Code White” following the incident. This is the language some employees confirmed to WUSA9 that they received via text and email alerts during Tuesday’s incident.

RELATED: Active shooter reports at Walter Reed hospital cause panic, confusion

A Code White exercise prepares staff members in case of an active shooter, according to

During a Code White drill, staff members are to shelter in place, secure doors and quiet devices. Law enforcement is also part of the exercise. They are trained to arrive at the scene and follow active shooter protocols. says staff members are trained to follow the direction of officers on-scene.

PHOTOS: Reports of active shooter at Walter Reed was a drill, Pentagon says

One of the more recent Code White drill at the Walter Reed Military Medical Center was in July, according to