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

Agent David “Chris” Maland died in a shooting following a traffic stop, the FBI said. A second person killed in the incident was a German national in the country on a current visa, authorities said.

The fatal encounter occurred around 3:15 p.m. EST Monday on Interstate 91 in Coventry, about 13 miles south of the Canadian border.