An FBI report published Monday says that 51 U.S. law enforcement officers were killed in the line of duty in 2014. Only 27 were killed in the line of duty in 2013.
The Washington Post notes that while the increase in officer deaths seems high, the number of officers who died in 2014 is "still lower than what the country has seen in recent decades." An average of 64 officers were killed each year from 1980 to 2014, so 2014's officer death report was below the average. The Post also notes that 2013's 27 officer deaths mark the lowest officer death toll since 1980.
Here's an explanation of the officer deaths by category, from the report:
By circumstance, 11 officers died from injuries inflicted as a result of answering disturbance calls (one of which was a domestic disturbance). Ten officers were conducting traffic pursuits or stops, eight were killed as a result of ambushes (six due to entrapment/premeditated situations and two during unprovoked attacks), and six officers were investigating suspicious persons or circumstances. Five officers sustained fatal injuries while they were performing investigative activities, four while they were engaged in tactical situations, three officers were handling persons with mental illness, and one officer was slain during a drug-related matter. Three officers were killed while attempting other arrests. [FBI]
Of the 51 officer deaths in 2014, guns were used in 46 of them, according to the report.