Update: Border Patrol Agent David Maland was fatally shot during a traffic stop confrontation with Teresa Youngblut and Felix Bauckholt in Vermont last week. The firearms involved were connected to suspects in homicide cases in Pennsylvania and California. Probe Details: Surveillance was initiated following sightings of the pair in tactical attire at hotels. Their vehicle was equipped with night-vision goggles, respirators, and phones wrapped in foil. Youngblut could potentially face life imprisonment upon conviction.