A 15-year-old student fatally stabbed a classmate and injured three others at a high school in the western French city of Nantes on Thursday before being subdued by teachers, police said.
The student who died was a girl and the three injured students were boys, BFM TV reported. Police did not confirm the age or gender of the victims.
It was unclear what led the student to carry out the attack.
One of the wounded was hospitalized in "very serious condition,″ Nantes Mayor Johanna Rolland told reporters.
Teaching staff overpowered the attacker at the Notre-Dame-de-Toutes-Aides, a private Catholic school, before law enforcement officials arrived, a police spokesperson said.
She said there was nothing to indicate a terrorist motive.
France's Prime Minister Francois Bayrou ordered tighter security outside and inside schools nationwide, and called for new proposals within four weeks for preventing and punishing knife violence by teens and children.
He said metal detectors at schools could be considered.
French President Emmanuel Macron praised the courage of the teachers who intervened, saying in a post on social media platform X that they ″undoubtedly prevented other dramas.″
Students were held inside the school after the midday attack but allowed to leave in the mid-afternoon under police protection. Dozens of parents waited outside.
"We're waiting to be able to hold them in our arms ... to help them deal with the stress this will have caused," said Nicolas, a parent at the school.
"A terrible drama happened at midday today, and my thoughts go first to the teenage girl who lost her life, and to the three wounded students" and their families, Education Minister Elisabeth Borne said.
The teachers "are in shock, and at the same time, very mobilized to return to class.''
A classmate of the boy told reporters that the attacker had expressed Nazi sympathies.
"He spoke of Nazi ideology. We thought he just said that to make people laugh. ... What we heard is that he wanted to bring back the Nazi ideas of Hitler," she told reporters outside the school.
The classmate also said that shortly before the attack, the attacker had sent a long email to the entire school.
French media published excerpts of the mail, which they said had an environmental and anti-globalization message but did not mention a possible attack.
Interior Minister Bruno Retailleau, a conservative, gave no details about the attacker's background or motives.
"The general climate of laxism and a lack of order and hierarchy is what leads to this kind of violence," he told reporters in Nantes.
Mayor Rolland, a socialist, said it was too soon to draw political conclusions.
"The mental health of the youth of this country is an issue that needs to be raised," she said.
The Nantes prosecutor will hold a news conference about the attack on Friday.
