Paris: French President Francois Hollande on Tuesday promised a tough response to a riot that devastated a deprived neighbourhood in the northern city of Amiens overnight.

“The state will mobilise all its means to combat these violent acts,” Hollande said after a night of unrest that left 16 police officers injured.

“Security is not only a priority for us, it is an obligation.”

Hollande’s Interior Minister Manuel Valls was due to visit Amiens later on Tuesday.

The riot, which the local mayor has linked to rising social tension against a backdrop of a deteriorating economy, cast a shadow over Hollande’s celebration of 100 days since he was elected.

Dozens of young men rioted in northern France after weeks of tensions, pulling drivers from their cars and stealing the vehicles, and burning a school and a youth centre.

The police department in Amiens says at least 16 officers were hurt by the time the riot ended Tuesday, some by buckshot.

At the height of the confrontation, 150 officers — both local and federal riot police — faced off against the young men throughout the neighbourhood. There were no arrests.

“The confrontations were very, very violent,” Amiens Mayor Gilles Dumailly told the French television network BFM. Dumailly said tensions had been building for a number of weeks between police and the impoverished residents, whom he described as “people who are in some difficulty.”

Police in Amiens said the riot involved about a hundred young men and began around 9pm Monday, ending around 4am after federal reinforcements arrived. It wasn’t immediately clear what caused the unrest, but there had been smaller confrontations with police over the past week, including one involving a weekend traffic stop that some local residents thought was unnecessarily violent.

Until Monday night the violence in Amiens had been on a smaller scale. By the time the latest confrontation was over, two school buildings had been burned, along with a dozen cars and trash cans used as flaming barricades. At least three bystanders were hurt when rioters yanked them from their cars, police said.

Earlier this month, the district in Amiens was among 15 areas declared the most troubled in France, and the government pledged more security and more money. Dumailly said he hoped tensions would improve with a plan to fix up the housing projects and offer more services.

Hollande was in the southeastern village of Pierrefeu-du-Var to pay tribute to two female police officers who were shot dead in the line of duty in June.

The visit was intended to underline the Socialist president’s support for the police and his determination to address public concerns over crime.

But it risked backfiring after the father of one of the two murdered policewomen denounced it as a public relations stunt.

Claude Berthaut, whose daughter Audrey was shot dead alongside her colleague Alicia Champlon, said: “I regret that he didn’t come before but has instead come for communications purposes 100 days after his election.

“In my mind, it is two months too late.”

Hollande sent an official from his private office to represent him at the funerals of the two officers, citing prior commitments.