According to law enforcement officials, an officer was killed after being stabbed during a scuffle at a transit station near the Pentagon on Tuesday.

The Pentagon, the US military's headquarters, was placed on lockdown after gunshots were fired near the building's entrance on Tuesday morning. According to officials who talked to The Associated Press on the condition of anonymity because they were not allowed to discuss the case, a Pentagon police officer who was stabbed subsequently died.

At a Pentagon press briefing, more information regarding the violence was expected. The link between the shooting and the officer's stabbing was not immediately apparent. The officials did not immediately release any additional information or a timeline of events.

According to the Pentagon Protection Force Protection Agency, the event occurred on a Metro bus platform at the Pentagon Transit Center. The complex is located in Arlington County, Virginia, just across the Potomac River from Washington, D.C., and is just feet from the Pentagon building.

Multiple gunshots were heard near the building by an Associated Press reporter, followed by a pause and at least one more shot. Another AP reporter overheard officers yelling "shooter."

According to a Pentagon statement, the facility was placed on lockdown due to "police activity." The Pentagon Force Protection Agency, which is in charge of security at the complex, tweeted soon before noon that the scene of the incident was secure. Except for the area surrounding the crime scene, the lockdown was removed.

At the time of the incident, Defense Secretary Lloyd Austin and Chairman of the Joint Chiefs of Staff Gen. Mark Milley were in the White House meeting with President Joe Biden.

Two Pentagon Force Protection Agency personnel were wounded in 2010 when a shooter approached them at a security screening area. The officers who were still alive fired fire, fatally injuring the gunman, John Patrick Bedell.