KAWASAKI, Japan—A man wielding two kitchen knives charged into a group of elementary-school girls waiting for a school bus in a Tokyo suburb, killing two people and injuring 16 others, officials said.

Police identified one of the dead as an 11-year-old girl, Hanako Kuribayashi, while an official at a Kawasaki hospital operated by Nippon Medical School said the other victim who died was a 39-year-old man. The assailant was also confirmed dead, public broadcaster NHK said.

Officials at the hospital of St. Marianna University School of Medicine said at a news conference that some of the victims they treated had multiple stab wounds.

Apparently referring to the attacker, they said a man in his 50s was declared dead at the hospital about three hours after the attack with stab wounds in his neck.

A motive for the attacks wasn’t clear.