According to reports, the attacker stabbed at least 15 children in a park in Kawasaki. A suspect has been arrested following the attack local media have reported. The attack took place at 07.44am local time (10.44pm BST).
As of yet, it is unclear as to the motive of the attacker on Tuesday morning.
According to local news outlet Nippon Hōsō Kyōkai (NHK), the attacker stabbed himself in the shoulder before being detained.
Police also confirmed that they discovered two knives.
Officials have confirmed that at least 15 people have been injured.
READ MORE: Japan earthquake: Scientists warn of an IMMINENT megaquake to strike
Moreover, roads around the area have been closed as emergency services have rushed to the scene.
Images from local broadcasters have shown emergency services setting up a crime scene and blocking off all surrounding roads.
Violent crime is rare in Japan but there have been sporadic high-profile attacks.
In 2010 there was another attack in a Tokyo suburb.
READ MORE: Japan emperor abdication: Why has Emperor Akihito abdicated?
The attack injured more than a dozen spree following a rampage on a school and commuter bus.
Two days before the attack, a 28-year-old man drove a truck in a pedestrian crossing.
As a result, three people died before another four were fatally stabbed.
The attack comes at a time when US President has visited the country and has become the first world leader to meet the country’s new Emperor.