On November 19, 2012, the Federal Bureau of Investigation (FBI) released the 2011 report, Law Enforcement Officers Killed and Assaulted (LEOKA).  In 2011, 72 officers were killed during duty, and 53 died in accidents while in the line of duty.  A total of 54,774 officers were assaulted with on duty.  

Statistics from LEOKA:

•    72 officers from city, institutional, county, state, tribal, and federal agencies were killed
•    50 city police officers were killed, the most out of any agency
•    the average age of an officer killed feloniously is 38, and the average length of service before death was     12 years
•    49 of the officers killed feloniously were on vehicle patrol
•    most the officers killed feloniously were slain with firearms, and 51 of the officers were wearing body     armor
•    seven officers were killed with rifles and six were killed with shotguns
•    six officers were killed by a vehicle used as weapon
•    two officers were killed with the hands, fists, feet, etc
•    39 of the 53 officers killed accidentally were killed in vehicle accidents
•    an average of 10.2 per 100 officers were assaulted

The majority of officer murders occurred in the South (29).  21 of the deaths occurred in the Midwest, while 10 occurred in the West and 10 occurred in the Northeast.  Two deaths occurred in Puerto Rico.  

68 of the police officers were Caucasian.  Three of the officers were African American, and one was American Indian.  Most of the officers were male, and three of the officer victims were female.  

Most the murders occurred when officers were in arrest situations (23).  15 of the officers were ambushed, 11 were engaged in traffic pursuits or stops, nine were engaged in tactically operations, and seven were responding to disturbance calls.  Additionally, five officers were slain while investigating suspicious activity.  On officer was conducting investigative activity such as a search or interview, and one officer was killed while transporting a prisoner in custody.  

Source: Federal Bureau of Investigation