French school protests have led to clashes between police and students in recent days. File photo of police at a protest last week

A 15-year-old boy's hand was blown off during a confrontation between police and demonstrators near a school in France, an official has said, as student protests continue across the country.

The "very serious incident" happened in the north-eastern city of Lens on Monday morning, according to the prefect of Pas-de-Calais, François-Xavier Lauch.

"The student's life is not in danger," he said, adding that the teenager was transferred "very quickly" to a hospital nearby.

Around 500 schools were partially or totally closed across the country on Monday amid student protests over the condition of school buildings and staffing which have led to clashes with police in recent days.

There are mixed reports in French media about how the boy came to sustain the injury.

AFP news agency, citing a police union source, reported that the student appeared to have picked up a sting-ball grenade fired by riot police, which exploded in his hand.

However, regional newspaper La Voix Du Nord quoted a girl who it said was near the teenager as saying he did not pick up the grenade.

"He didn't pick it up. I was there, I saw it. He didn't pick it up, he didn't catch it," she was quoted as saying.

When asked about the incident, Lens Mayor Sylvain Robert said the circumstances still needed to be clarified.

"Like you, and like many others, I have seen some videos showing the aftermath. But I did not see how the operation was organised, either by the police or by the students," he told French media.

A regional prosecutor said an investigation would be carried out by the French police watchdog, the General Inspection of the National Police (IGPN), "so all light can be shed on what happened".

The incident took place close to the Auguste Béhal high school, the prefect said.

Lauch said a "larger gathering" of students than on previous days had assembled outside the school.

"At the start of the morning, they threw various projectiles at the local police officers who were on site initially. When I say projectiles, I mean stones, fireworks, and mortars," he told French media.

"Instructions were given by the interdepartmental director of the National Police, naturally with my approval, to deploy a company of riot police (CRS) here to maintain order, and it was in this context that this event occurred."

The school issued a statement on Monday morning, saying: "In light of the events that took place this morning and in order to ensure the safety of the entire school community, the institution is switching to distance learning from now on.

"In addition, to support everyone during this period, a listening and support unit has also been set up at the establishment."

According to education minister Édouard Geffray, at least 190 students have been injured since the protests began.

Last week, Eden, 14, was badly hurt in Saint-Ouen-l'Aumône after reportedly being struck in the head by a tear gas grenade.

The student suffered "a double jaw fracture" and had to undergo "extremely major surgery", according to his lawyer. Interior Minister Laurent Nuñez has announced an investigation.

Speaking at a news conference on Monday, Eden's mother said her heart was "shattered".

"His jaw is wired shut. He can't eat except through a straw and only liquids," French media outlet BFMTV reported her as saying.

"It's shameful, it's appalling, it's violent, it's horrific," she said, adding: "This should not happen. They are dealing with children who are asking for better conditions in which to study."

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