Protests and unrest erupted in the Paris region overnight after police shot dead a 17-year-old who failed to stop when ordered to by traffic police.

Video circulating on social media shows a police officer pointing a gun at the driver of a car, before a gunshot is heard. The car then crashes to a stop.

The teenager, named as Nahel, died of bullet wounds in the chest despite help from emergency services.

The officer accused of shooting him has been detained on homicide charges.

The shooting triggered a series of protests on Tuesday night in Nanterre, the area just west of Paris where the teenager was killed. Some 31 people were arrested following the disorder.

Nahel is the second person this year in France to have been killed in a police shooting during a traffic stop. Last year, a record 13 people died in this way.

According to French media, police initially suggested the teen drove his car towards them with the intention of hurting them.

But footage posted online and verified by the AFP news agency tells a different story.

It shows two officers at the vehicle. One points his weapon at the driver through the window and appears to fire at point-blank range as he tries to drive off.

The agency also reports that a person in the video can be heard saying "you're going to be shot in the head" - but it is unclear who says it.

Two others were in the car at the time of the shooting - one fled while another, also a minor, was arrested and held by police.

The incident sparked anger and disorder overnight, with cars and rubbish bins set alight and bus shelters destroyed. Fireworks were also set off near the police station. Riot police used tear gas to break up protesters, some of whom created barricades throughout the night.

Several incidents of unrest were also recorded in the towns of Asnières, Colombes, Suresnes, Aubervilliers, Clichy-sous-Bois and Mantes-la-Jolie.

Authorities have opened two separate investigations following the teen's death - one into a possible killing by a public official, and another into the driver's failure to stop his vehicle and the alleged attempt to kill a police officer.

Paris police chief Laurent Nuñez told French television station BFMTV that the policeman's actions "raises questions", though he suggested the officer may have felt threatened.

The 17-year-old's family lawyer Yassine Bouzrou insisted that was an illegitimate defence, telling the same channel the video "clearly showed a policeman killing a young man in cold blood".

He added that the family had filed a complaint against police for "lying" - after initially claiming the car had tried to run down the officers.

Another lawyer representing the victim's family, Jennifer Cambla, told local media that nothing could justify what had happened, and described the death as an "execution".

In a video posted on TikTok, Nahel's mother Mounia urged people to join her on a march for her son.

"Come all, I beg you", she said. "We will all be there."

"I'm hurting for my France. An unacceptable situation. All my thoughts go out to Nahel's family and loved ones, this little angel gone far too soon," France and Paris Saint-Germain striker Kylian Mbappé wrote on Twitter.

Lupin actor Omar Sy tweeted that his "thoughts and prayers go out to the family and loved ones" of Nahel.

"May justice worthy of the name honour the memory of this child."

France's President Emmanuel Macron called Nahel's killing "inexplicable" and "inexcusable", adding that the case had "moved the entire nation."

"Nothing justifies the death of a young person," he said, calling for "calm for justice to be done".

"I want to say that in no case is an act like the one we have seen justified - if the inquiry should confirm the videos we have seen," Mr Darmanin told French media on Wednesday.

"We hope to have the whole truth of what happened," he said.

Left-wing leader Jean-Luc Mélenchon expressed his "heartfelt condolences" to the family of the teen. "No officer has the right to kill unless in self-defence," he wrote in a tweet.

"This uncontrolled police force discredits the authority of the state. It needs to be completely overhauled," he added.

Two weeks ago, a 19-year-old driver was shot dead by police in the western France town of Angouleme, after allegedly hitting an officer in the legs during a traffic stop.