Grasse shooting: Headmaster and children among three injured in attack at French school

Authorities say incident believed to be personal dispute and is not terror-related

A teenager boy has been arrested after three people were shot in an attack on a school in Grasse, southern France.

Police detained the 17-year-old student at the Lycee Alexis de Tocqueville, where the headmaster was among those shot.

He was armed with a rifle, a revolver, a pistol and grenades according to local newspaper Le Dauphiné Libéré.

Investigators said three people were shot in the assault, which left five others being treated for shock. None of the injuries are believed to be life-threatening.

A French government attack alert relating to a shooting at a high school in the southern French town of Grasse. (AFP/Getty Images)

Emmanuel Ethis, the rector of the Nice Academy educational district, said two children had been wounded and their parents were informed.

A student called Thomas told Nice Matin he saw the attacker shoot the headmaster twice using the shotgun.

"He was incredibly cool," he added. "He remained calm even after being hit by the first shot. Despite a bullet in his arm, he kept trying to reason with him."

Other pupils said the suspect was known for watching "strange videos" online, including battle footage and executions.

A witness interviewed by France Inter radio said the students heard a bang and took cover under classroom tables.

“I went to close the windows and saw a guy who looked at me in the eyes. He seemed to be a student and not very big. He shot in the air and ran away,” the student said without giving his name.

A local resident said he saw crowds of students fleeing down the street, jumping over the gates and walls in scenes of panic.

There was confusion over how the attacker managed to take weapons into the school, where students go through bag searches at the entrance.

Christian Estrosi, president of the regional council of Provence-Alpes-Côte d'Azur, said the school principal was injured but gave no information on his condition.

"I have just been talking with Francois Hollande," he added. "Several people have been injured but the exact circumstances remain unclear at this stage."

A spokesperson for the local council in Grasse said the incident resulted from a personal dispute and was not believed to be terror-related.

France's elite "Raid" armed police force secured the scene, with the education minister and local officials visited pupils, teachers and the emergency services.

French policemen stand at the Tocqueville high school in the southern French town of Grasse (Getty Images)

The incident triggered a red alert on France's Vigipirate terror warning system, with all schools in Grasse temporarily put on lockdown as a precaution.

A spokesperson for the French interior ministry said a "public security event" was underway at the school and asked people to follow the instructions of local authorities.

"Do not pick your children up from school," read a message to local parents. "They are being taken care of by school staff and emergency services."

The incident came shortly after an explosion at the International Monetary Fund's offices in Paris, where a suspected parcel bomb injured a woman.

France has been under a state of emergency since Isis militants massacred 130 people in Paris in November 2015.

The country has since been hit by several atrocities inspired by the terrorist group, including the Nice lorry attack and murders of a police officer and Catholic priest.

The attacks have put security at the top of the agenda for France's upcoming presidential election, where centre-left candidate Emmanuel Macron is predicted to beat far-right leader Marine Le Pen.