Military base near DC on lockdown, active shooter report

In this photo taken July 15, 2016, President Barack Obama rides in his limousine as he arrives at Joint Base Andrews, Md. Joint Base Andrews tweets that the base is on lockdown due to a report of an active shooter. The tweet sent Thursday, June 30, 2016, instructs all personnel at the base in Washington's Maryland suburbs to shelter in place and says more information will be released as it comes. (AP Photo/Jose Luis Magana) (The Associated Press)

The Malcolm Grow Medical Center is seen at Joint Base Andrew, Md., Thursday, June 30, 2016. The military post near Washington said a lockdown was lifted Thursday except for a medical building where an active shooter was reported earlier in the day. Joint Base Andrews said in a tweet that the all-clear was given for the base except for the medical building. The base did not say why the Malcolm Grow Medical Facility remained on lockdown. (AP Photo/Carolyn Kaster) (The Associated Press)

The Malcolm Grow Medical Center is seen at Joint Base Andrew, Md., Thursday, June 30, 2016. The military post near Washington said a lockdown was lifted Thursday except for a medical building where an active shooter was reported earlier in the day. Joint Base Andrews said in a tweet that the all-clear was given for the base except for the medical building. The base did not say why the Malcolm Grow Medical Facility remained on lockdown. (AP Photo/Carolyn Kaster) (The Associated Press)