Two Deputy U.S. Marshals and four U.S. Marshal Task Force Officers have been killed since January.
The most recent death, on Monday, when 48 year old U.S. Marshal, John Perry, was killed while trying to serve a warrant.
Deputy U.S. Marshals and Task Force Officers arrested 120,000 fugitive felons last year, and around half of those were violent offenders.
Kevin Scott, Deputy U.S. Marshal, says "We must ensure we continue to protect our communities through the arrest of dangerous felons, many of whom are armed and dangerous, but we must also address the security risk they pose to our law enforcement personnel"
The U.S. Marshal's service says they will continue training and equipping Deputies and Task Force Officers to reduce the risk to their safety, as they continue the brave service they provide every day.