A Washington state woman has been ordered to be held without bail in connection with the death of a U.S. Border Patrol agent in Vermont.

The weapon that killed Agent David Maland last week in northern Vermont was bought by a person of interest in a double murder two years ago in Delaware County, state police say.

Teresa Youngblut, 21, faces federal firearms charges in the Jan. 20 death of Agent David Maland. She’s accused of opening fire on agents during a traffic stop in northern Vermont, sparking a shootout that also left her companion, Felix Bauckholt, dead.