US Air Force Joint Base Andrews, located in Maryland state, east of Washington, has been put on lockdown due to an 'active shooter' alert. 

The base was to conduct a shooting exercise, but there was reported a real-life active shooter situation at Malcolm Grow medical facility at approximately 9 a.m. local time June 30, 2016.

“The call occurred during an exercise. Because the report came in as a real active shooter we have to respond accordingly. We are treating as if it is and no further information at this time," said Joint Base Andrews spokesperson.

The base is located 20 miles from Washington and is home for the US Presidential aircraft – Air Force One. White House reported that President Obama was at the base last night, returning from a trip to Ottawa. Vice- President Joe Bidden was arranged to fly out of the base at noon on Thursday, but the incident has delayed the trip.