Tokyo police said on Thursday a man has been charged with attempted murder after a knife attack on the subway that reportedly injured two people during rush hour the previous day.

Yoshitaka Toda, 43, was arrested on Wednesday evening at Todai-mae Station in the Japanese capital on suspicion of assaulting a man in his 20s, a police spokesman said.

The suspect "with the intent to kill slashed the victim in the head and other parts of the body with a knife-like object that he was carrying, causing injuries," the spokesman said.

Local media said Toda allegedly attacked the victim several times – first on the station's platform, before the victim dashed inside a subway car where Toda chased him and slashed him in the head several more times.

Other passengers apprehended Toda, who was arrested by officers on the spot, reports said.

Toda and the victim are not believed to have known each other, local media said, adding that one other passenger who helped apprehend the attacker was also cut in the hand.

Violent crime is relatively rare in Japan, which has a low murder rate and some of the world's toughest gun laws.

But there are occasional stabbing rampages and even shootings, including the assassination of former prime minister Shinzo Abe in 2022. (AFP)