At least one person was killed and another injured in Marseille on Monday when a van crashed into two bus shelters in different parts of the French city, police said, in an incident not being treated as terrorism at this stage.
Police advised the public to avoid the Old Port area where the driver, a 35-year-old man, was arrested.
A source close to the investigation told Reuters the suspect was known to police for minor crimes and had psychological issues. France's counter-terrorism prosecutor said it had not taken up the case at this stage.
"The arrest was made in a surprisingly calm fashion, no gunshots were exchanged," David Reverdy, of the Alliance police union in Marseille, told BFM TV.
The driver first hit a bus shelter around 8:15 a.m. (0615 GMT) in the poorer northern part of the city, before ramming into a second one an hour later, several kilometers (miles) to the south.
"The distance traveled by the driver suggests a certain determination," Reverdy said.
But we can ask ourselves: why these places? If one wanted to cause carnage, other places in Marseille, at another time of day, would have been more logical," he said.
The incident comes as Spanish police hunt for a 22-year-old suspect they believe was behind the wheel of a van that plowed through crowds in Barcelona on Thursday, killing 13.
France has been under a state of emergency since Islamist militants killed 130 people in and around Paris in November 2015. Another 86 people were killed in an attack in Nice in July last year, when a Tunisian man drove a truck along the seafront boulevard, mowing down Bastille Day revelers.