Passers-by prayed and placed flowers on a busy Tokyo shopping street yesterday where seven people were killed the day before in a stabbing rampage, as Japan tried to make sense of the attack and others like it.

Police arrested a blood-spattered 25-year-old man who they said drove a truck into a crowd of people, then got out and began a frenzied knife attack. The killings follow a string of similar incidents in recent months, shocking Japan and sparking talk of failing communities and declining morality in a country proud of its low crime rate. The suspect in Sunday?s attack lived alone and had a temporary job at a car factory.

Media said he had warned on a mobile phone messaging board that he was heading to Akihabara, Tokyo?s biggest electronics shopping district, to kill people.