Overnight violence in French cities has halved in 24 hours, the interior ministry said Tuesday, a week after riots erupted over the police killing of a teenager at a traffic stop.

Seventy-two people were arrested overnight nationwide, including 24 in and around Paris, and 24 buildings torched or damaged, it said.

A statement said 159 vehicles had been set ablaze, and 202 fires set in rubbish bins or elsewhere in public areas.

Four offices of police or gendarmes came under attack, but there were no injuries.

Police mobilisation had been kept at the same level as the two previous nights, at 45,000 in all of France.

The government has battled riots and looting since 17-year-old Nahel M. was killed by an officer during a traffic stop on Tuesday just outside Paris, rekindling long-standing accusations of systemic racism among security forces.

Mayors across France held rallies Monday calling for an end to the violent clashes.

Monday's demonstrations calling for a "return to republican order" came after the home of the mayor of a Paris suburb was rammed by a burning car, prompting widespread outrage. 

A total of 157 people had been arrested overnight Sunday to Monday -- already a sharp decline from the number held the night before.

President Emmanuel Macron was on Tuesday to meet with the mayors of 220 municipalities that suffered damage during the riots.

Macron hopes to "start the painstaking, long-term work needed to understand the profound reasons that led to these events", an official at the president's office said. 

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