Washington, March 31 (IANS): A person was shot dead by security personnel, while another was injured when they tried to drive into the National Security Agency (NSA) campus in the US, without authorisation, according to media reports on Monday.

The two men, dressed as women, tried to ram the main gate of the NSA headquarters at the Fort Meade military installation in the US state of Maryland, officials said, according to a CNN report.

"Shortly before 9.00 a.m. today (Monday), a vehicle containing two individuals attempted an unauthorised entry at a National Security Agency gate," Jonathan Freed, NSA director of strategic communications, said in a statement.

"The driver failed to obey an NSA police officer's routine instructions for safely exiting the secure campus. The vehicle failed to stop and barriers were deployed."

Police fired on the vehicle when it accelerated towards a police car blocking its way, according to the NSA.

One of the two occupants of the vehicle died on the spot, the report said, adding that the other was injured and hospitalised. An NSA police officer also sustained injuries in the incident and was hospitalised.

Investigators are looking into whether the two intruders were under the influence of drugs, a federal law enforcement official said.

A man reported his car stolen from a hotel not far away from the NSA headquarters and said that he had been with two men who had taken his car. Cocaine was found in the intruders' vehicle.

The US Federal Bureau of Investigation (FBI) said on Monday that it was conducting an investigation with NSA police and other law enforcement agencies, and interviewing witnesses on the scene.

The FBI said that it did not think that the incident was related to terrorism.

"We are working with the US Attorney's Office in Maryland to determine if federal charges are warranted," the FBI said in a statement.

White House Principal Deputy Press Secretary Eric Schultz said that US President Barack Obama had been briefed on the incident.

This was the second security incident this month involving the NSA. In early March, a former state correctional officer was arrested, accused in a string of Maryland shootings, including one at Fort Meade.

Fort Meade is a highly sensitive area in the US. In addition to the headquarters of the NSA, it is home to 95 units from all branches of the armed forces and offices that report to several defence department agencies, according to the US Army, which operates the base.