Andrews Airbase, the military facility that services Air Force One, was placed on lockdown on Thursday because of a report of an active shooter, the Joint Base Andrews said on Twitter.

All personnel at the base, located in Maryland just outside Washington, DC, were instructed to remain in place, USA Today reported.

'JBA is currently on lockdown due to a report of an active shooter. All personnel are directed to shelter in place. More info as it comes,' read the tweet from Joint Base Andrews.

Joint Base Andrews had planned drill today. Unclear if shooter is related to the drill. First responders are on-scene now, US media reports.

The incident is ongoing at the Malcolm Grow Medical Facility.