A 15-year-old female junior high school student has died after she and a boy were stabbed Saturday at a McDonald's restaurant in Kitakyushu in Fukuoka Prefecture in southwest Japan, according to local police.

The assailant, a man around 40 years old and about 170 centimeters tall, is on the run after the incident, the police said Sunday.

The injured boy, who is in the same grade at the same school as the girl, said they were "stabbed by a complete stranger." The girl, Saya Nakashima, died late Saturday in hospital. The boy's injury is not life-threatening, police said.

According to the police, the man was wearing a gray top, black pants and what appeared to be yellow footwear. It remains unclear whether he had any connection to the slain girl.

The police said security camera footage showed the man stabbed the two students within a minute of entering the restaurant as they were waiting in line at the cash register at around 8:30 p.m. He remained silent during the attack.