UPDATE - US: Active shooter at Joint Base Andrews

UPDATES WITH JOINT BASE STATEMENT

By Michael Hernandez

WASHINGTON (AA) - Joint Base Andrews, the home base for Air Force One, has been placed on lockdown Monday morning amid an active shooter situation.

The incident is ongoing at the Malcolm Grow Medical Facility, the base said on Twitter just after 9 a.m. local time (1300 GMT), and all personnel have been ordered to shelter in place.

First responders are on the scene.

The base was scheduled to conduct an active shooter exercise, but a call of a real world shooter prompted the emergency response.

"Because the report came in as a real active shooter we have to respond accordingly," the base said in a statement.

When contacted by Anadolu Agency, Joint Base Andrews could not confirm if the exercise was to take place at the medical facility.

The base is located in Prince George's County, Maryland, just outside of the nation's capital.

This story is developing.