ARLINGTON (WDVM) — An officer died after being stabbed Tuesday during a burst of violence at a transit station outside the Pentagon, and a suspect in the incident was shot by law enforcement and died at the scene, AP reported.

The Pentagon, the headquarters of the U.S. military, was temporarily placed on lockdown after gunshots were fired Tuesday morning around 10:37 a.m. near the entrance of the building. A Pentagon police officer who was stabbed later died, according to officials who were not authorized to discuss the matter, and spoke to The Associated Press on condition of anonymity.

At one point, Metro subway trains were ordered to bypass the Pentagon due to police activity and investigation.

Secretary of Defense Lloyd Austin III said in a statement that flags will be flown at half-mast in honor of the fallen officer. The statement said, “This fallen officer died in the line of duty, helping protect the tens of thousands of people who work in – and who visit – the Pentagon on a daily basis.”

The suspect involved has been identified by multiple law enforcement officials as Austin William Lanz, 27, of Georgia. According to officials, Lanz ambushed the officer and stabbed him in the neck, responding officers then shot and killed Lanz.

Pentagon Force Protection Agency has identified the deceased officer as George Gonzalez, a native of Brooklyn, New York. According to officials, Gonzalez was a graduate of New York City’s Canarsie High School and joined the agency as a police officer on July 22, 2018.

The motive behind this incident is still unclear.

The Associated Press contributed to this story.