Fort Meade (US): A firefight erupted on Monday when two people in a car tried to ram a National Security Agency gate at the Fort Meade military installation, killing at least one person, according to preliminary reports cited by two US officials.
An FBI spokeswoman said the incident was not believed to be linked to terrorism.
The two federal officials said at least one of the people in the car died after the firefight ensued. Both spoke on condition of anonymity because they were not authorised to discuss an ongoing incident on the record.
The NSA is headquartered on the sprawling Army installation near Baltimore.
FBI spokeswoman Amy J Thoreson said in an email today that the shooting scene is contained. The agency is working with the US Attorney's Office in Maryland to determine if federal charges are warranted, she said.
Thoreson also says FBI agents are doing interviews with witnesses.
Local television showed two damaged vehicles near a gate and emergency workers loading an injured uniformed man into an ambulance.
Aerial news images showed that one of the damaged vehicles was a white SUV marked "NSA Police". Its front end was crumpled, and the hood was up. The other was a dark, unmarked SUV.
A building on the NSA campus was damaged by gunfire earlier this month. Authorities captured a man March 3 who they believe fired that night on the NSA site, as well as earlier at several nearby places and two moving vehicles. The suspect in that case, Hong Young, told police he heard voices directing him to fire on one of the occupied vehicles.