The suspect said initially that it was an "act of terror," according to Japan's national television station, NHK.
A man plowed his vehicle into crowds celebrating New Year's Day in Tokyo shortly after midnight, injuring at least eight people, one in serious condition.
The 21-year-old driver, Kazuhiro Kusakabe, originally from Osaka, has been detained, according to a police spokesman. Japan’s national broadcaster NHK said Kusakabe was arrested on suspicion of attempted murder.
NHK said the suspect had initially described the incident in the popular tourist area of Harajuku in central Tokyo as an "act of terror" but later said the attack was in retaliation for capital punishment.
"I can't believe it, this is a place I'm familiar with, so it's very shocking," said Tatsuhiro Yaegashi, a 27-year-old worker in the area.
Kusakabe fled from the scene and assaulted a passerby before he was captured 20 minutes later, NHK said. About 5 gallons of kerosene were found in the car.
The street was closed to vehicles at the time of the attack to accommodate a large number of pedestrians making their way to the shrine for New Year's prayers.
TV images of the scene Tuesday showed a gray colored vehicle positioned across the street, which the suspect was driving. The front of the vehicle was badly damaged and dozens of police and rescue officials were at the scene.
"I learned about the incident later. But I shudder to think. If the incident had happened five minutes later, I would've been involved," a woman who walked past the scene shortly after the incident told NHK.
In a similar attack in 2008, a man who said he was tired of life drove a rental truck into a crowd of pedestrians in Tokyo before jumping out and stabbing several people, killing at least seven people and injuring a dozen others.