The National Police Agency on Friday clarified remarks made by chief Setsuo Tanaka on Thursday that were interpreted as indicating he was concerned that the ability of the Japanese police to prevent crime is weakening.

The agency said Tanaka actually suggested that Japanese society has lost its ability to prevent crime.

Tanaka was referring to a series of serious crimes committed since late last year, including the killing of a family of four in Tokyo's Setagaya Ward on New Year's Eve.