A U.S. Border Patrol agent killed during a traffic stop near the Canadian border worked security duty at the Pentagon during the time of the Sept. 11 attacks.

Federal agents are investigating after a US Border Patrol agent was shot and killed Monday afternoon on the highway in Vermont.

David "Chris" Maland, 44, was fatally shot in the line of duty on Tuesday in Coventry, Vermont, according to the Vermont State Police. Maland was an agent with the U.S. Border Patrol Swanton Sector and was conducting a traffic stop at the time.