One person has died and another was injured after a van crashed into two bus shelters in different parts of Marseille an hour apart.
Police urged people to avoid Boulevard Charles Livon in the Old Port area of France's second-largest city, where the 35-year-old male driver was arrested.
He is said to have psychological issues and be known to police for minor crimes.
Authorities said the incident was not being treated as terrorism.
The first bus shelter was hit by a Renault Master van in the northern part of the city at around 8.15am local time, before a second bus shelter in front of a KFC restaurant was hit an hour later around three miles (5km) away.
French media reported one person was hospitalised after the first collision, while a woman in her 40s died following the second incident.
Police were seen securing an area of Marseille as forensic officers investigated.