Breaking news. One dead and three injured in Nantes high school stabbing, police say

At least one person has been killed and three others seriously injured in a knife attack at a school in the western French city of Nantes, police say.
According to police sources, several people were stabbed by a fellow student.
The alleged attacker was arrested at the scene after being restrained by a member of the teaching staff.
The French radio station Europe1 said the attacker allegedly stabbed a female student after an argument on the second floor of the high school before stabbing three others on the first floor.
Our journalists are working on this story and will update it as soon as more information becomes available.