By Chris Hogg
BBC News, Tokyo
A bouquet of white lilies is lying on the side of the road at a busy intersection in the Akihabara district of Tokyo.
There was shock and confusion at the scene of the stabbings
It marks the spot where Tomohiro Kato, a 25-year-old from the town of Susuno, about 100km (60 miles) from Tokyo, went on the rampage among Sunday lunchtime shoppers.
Reports say Mr Kato drove up to the intersection in a large white van and knocked over several pedestrians.
One witness described how he leapt out of the cab and stabbed a man he had already driven into several times. He then went after others in the crowd.
Grainy mobile phone camera footage captured seconds later shows the desperate efforts of passers-by to tend to those injured.
Half an hour after the attack medical staff were still trying to treat those injured in the middle of the road.
Behind hastily erected green tarpaulins, paramedics tried desperately to revive those who had been attacked.
Towels and umbrellas were scattered around where they had been dropped in the chaos.
A few hours later the area had been cleared. There were pools of water on the side of the road where the blood had been washed away.
The electronics store nearest to the intersection was closed.
In front of it bystanders were reading special single sheet editions of a newspaper which detailed what had happened, with photographs of the emergency services working at the scene.
There was still a sense of shock. Foreigners were asking journalists what was going on. Japanese people were taking photographs. Some were just staring.
One young man stood silently, his hands clasped together in prayer, his head bowed. He was surrounded swiftly by Japanese reporters who wanted to know what he thought of the incident.
It is still too early to say what provoked the attack. Reports say the suspect told police he had come to Akihabara because he wanted to kill people.
Japanese television networks broadcast news flashes each hour throughout Sunday afternoon, updating their audiences as the tragedy unfolded.
But there has been little comment in the media here so far about why incidents like this happen.
Japan is still comparatively safe, compared to other countries in the world.
But there have been other similar stabbing rampages here earlier this year.
In January a 16-year-old boy attacked five people with kitchen knives, injuring two of them, in a Tokyo shopping street.
A man wanted by police on suspicion of murder stabbed passers by with a knife at a railway station in Tsuchiura in March, injuring eight people, one of whom later died.
There are some here who fear this country is becoming a more violent place, even though the levels of violent crime are still so far below those of other countries.
They blame the pressure people feel under - Japanese society can be intolerant of failure, or of difference.
If you do not fit in, do not get a job or do not behave like everyone else you can be ostracised.
Many worry too about growing inequality here.
The scenes are reminiscent of a 1995 subway gas attack
People on the margins of society see a greater gap between themselves and those in work than perhaps there was before.
The television pictures of the paramedics treating casualties in a busy street will recall for some the sarin gas attacks on the Tokyo Metro System in March 1995 that left 12 dead and many more than 5,500 injured.
This would appear to be a something quite different, on nothing like the same kind of scale.
The suspect is reported to have told police he was acting alone. He is quoted as saying he was "tired of life".
But inevitably once the focus shifts from the plight of those victims still being treated back to the attacker, questions will be asked about what could have driven a man to murder passers-by in a busy shopping street.
Can it be explained away as the action of a deranged individual which could not have been foreseen or prevented?
Or is it a symptom of something more disturbing in Japanese society, pressure or stress so great that it drives troubled people to commit terrible acts with tragic consequences?