Police have taken the student into custody, according to the Bayonne prosecutor.
A senior government official, who requested anonymity because he was not authorized to speak about the situation in public, said the initial information shared by police suggests the attacker has serious mental health difficulties.
According to French media, the student, who was born in 2007, said that voices had commanded him to murder the 53-year-old Spanish instructor at the private Catholic school in Saint-Jean-de-Luz.
Later on Wednesday, Education Minister Pap Ndiaye was scheduled to visit the school.
Following a weekly Cabinet meeting, French government spokesman Olivier Veran expressed the government’s support for the education community and said the event represents a trauma for the nation.
In 2020, teacher Samuel Paty was killed outside his school in suburban Paris by an 18-year-old refugee of Chechen origin who was angry that he had shown caricatures of the Prophet Muhammad in class after the images were re-published by a satirical newspaper targeted in a 2015 attack.