France, April 19 -- A 14-year-old girl has died of a heart attack in eastern France after her school locked down to protect itself from a knife attacker who lightly wounded two other girls, an official said on Friday.

The teenager "was rescued by teachers who were very fast to call the fire department. She died at the end of the afternoon," education official Olivier Faron said.

The girl's middle school in the village of Souffelweyersheim closed its doors on Thursday afternoon after a man stabbed two other girls aged 7 and 11 outside a nearby primary facility.

"Sadly this pupil underwent an episode of very high stress that led to a heart attack," Faron said.Lockdown terror

A mother outside the middle school on Friday morning said her ...