France has suspended the use of stun grenades for policing student protests after a 15-year-old boy's hand was blown off earlier this week in Lens.

Interior Minister Laurent Nuñez said he had requested the pause until the facts of the incident had been "clarified".

Rights groups have complained of police using disproportionate force towards teenagers who have been protesting against old buildings, a lack of teachers and overcrowded classrooms all week.

Police unions have said they need non-lethal options such as stun grenades to protect officers in these increasingly violent situations.

Watch: Riot police clash with school protesters and use tear gas in France

Watch: Bin on fire at school protests on the streets of Lille