French president Francois Hollande vowed to take control of the situation, which reportedly bubbled up from police searches of local residents.
Youths fired buckshot at police in clashes in the French city of Amiens overnight on Tuesday, torching cars and a nursery school in a resurgence of urban unrest that President Francois Hollande said he would do everything to confront.
Hollande dispatched his Interior Minister Manuel Valls to the northern city, where two nights of violence were apparently sparked by tension over spot police checks on residents.
Officials said 16 police officers were hurt in the disturbances, some struck by buckshot others hit by a hail of missiles thrown by around 100 youths who gathered in northern districts of Amiens.
One officer was in a serious condition, the city's Socialist Mayor Gilles Demailly told Reuters.
Speaking during a visit to southeastern France, Hollande said the state would "mobilise all its resources to combat this violence", which has shaken depressed quarters of major French cities at regular intervals.
"Security resources have sadly be declining for too many years," said Hollande. "Our priority is security which means that the next budget will include additional resources for the gendarmerie and the police."
Reinforcements were being dispatched to the suburb, parts of which had already classified as a "priority security zone" in need of extra policing. The policy formed part of the Socialists' election campaign pledge on law and order.
The unrest was the first major law and order test for Hollande's ruling Socialists following his May election victory over conservative incumbent Nicolas Sarkozy, whose tough policies on crime and immigration some critics said fanned urban unrest.