A man swinging a knife attacked commuters who were waiting at a crowded bus stop just outside Tokyo during Tuesday morning's rush hour, wounding at least 19 people, including 13 children, Japanese authorities said, according to The Associated Press.
Media reports said that two people were killed, though the local fire department reported one death.
The AFP news agency reported that one child as well as the suspected attacker were dead.
The victims were lined up at a bus stop near Noborito Park in Kawasaki City when the man attacked. NHK national television, quoting police, said the wounded were rushed to nearby hospitals.
No other details, including the man's identity and motives, were immediately known.
US President Donald Trump, who is on a visit to Japan, sent his condolences to the victims of the attack.
"On behalf of the First Lady and myself, I want to take a moment to send our prayers and sympathy to the victims of the stabbing attack this morning in Tokyo. All Americans stand with the people of Japan and grieve for the victims and their families," he said.
Although Japan has one of the lowest crime rates in the world, it has had a series of high-profile killings, including in 2016 when a former employee at a home for the disabled was accused of going on a stabbing spree that killed 19 and wounded more than 20 others, noted AP.
In 2008, seven people were killed by a man who slammed a truck into a crowd of people in central Tokyo's Akihabara electronics district and then stabbed passers-by.
In 2001, a man killed eight children and wounded 13 others in a knife attack at an elementary school in the city of Osaka. The incident shocked Japan and led to increased security at schools.