The mayor of the town of Grasse in southern France says one pupil has been arrested and another is on the run after a shooting at a school.
He told reporters they intended to target another student, and the headteacher has been injured after intervening.
Local officials say it isn’t terrorist related, but the French government has issued a nationwide alert.
People in the town, which is about 25 miles from Nice, are being advised to stay indoors.
Separately, French police say a letter bomb’s exploded at the offices of the International Monetary Fund in Paris.
One employee suffered minor hand and face injuries.