PARIS: French authorities have announced plans to ban social media for under-15s and the sale of knives to minors after the murder of a teaching assistant by a 14-year-old boy plunged the country into shock.

A secondary school pupil was arrested on Tuesday after killing a 31-year-old school assistant with a knife during a bag search in Nogent in eastern France.

Friends and well-wishers left flowers and messages of support in front of the secondary school struck by the tragedy.

“We share your pain,” read one message.

Laurence Raclot, who knew the teaching assistant, Melanie, said she was “stunned.”