The legal revisions were made last November after a dagger was used in a random attack in Akihabara in June 2008, which left seven people dead and 10 others injured. The ban covers double-edged knives, including daggers, with blades measuring 5.5 centimeters or longer. Offenders may receive a prison term of up to three years or a fine of up to 500,000 yen. Police have already taken action in 11 cases where people were caught carrying such knives, an act not covered by the grace period. Calling on owners to voluntarily hand in knives, they initially collected about 500 blades a month, but received about 8,600 in the last month.

Gee whiz, it sucks to be a subject ...