Police nationwide logged 1,097 cases of murder, attempted murder and murder plots last year, down 200 from the previous year and marking the fewest on record in the postwar era, the National Police Agency said in a preliminary report Friday.

After peaking at 3,081 in 1954, the number of cases of murder, attempted murder and murder plots recognized by the police after reports or complaints by victims or others, has dropped to one-third of this figure.

"The reason for the decline is not known as the motives have not been analyzed nationally," an agency official said.

The number of all criminal cases was about 1.7 million last year, down 6.3 percent from the previous year and posting the seventh decline in a row, according to the agency.