From the Union Pacific Railroad Officer Down Memorial Page:
- Monday, August 19, 1878: Special Agent Robert Widdowfield and Special Agent Henry Vincent were killed when they were ambushed while pursuing a suspect from a train robbery in Carbon, Wyoming. As the officers approached the suspect's campsite they were ambushed by the suspect. The suspect was later arrested and sentenced to death for the murders. Before being executed he was lynched by an angry mob.
- Saturday, July 9, 1977: Special Agent Boles was shot and killed after interrupting a burglary in progress in Denver, Colorado. Agent Boles called for backup, but by the time they arrived Agent Boles and been shot and killed by the suspect. The suspect was later arrested and convicted for Agent Boles' murder and served 15 months on a reduced charge.