UPDATE 1.05pm: A man suspected of ramming his white van into two bus stops in the southern French city of Marseille, killing a woman, is being treated for psychological problems, officials said.
The suspect, who has not been identified by name, is 35 years old and from the Grenoble region in eastern France, a press official for police headquarters in Marseille said.
The official said specialists were going over the van for clues about the suspect's motives as he was being questioned.
Police and forensic experts in white suits took evidence from the bus stop.
The glass walls of the bus stop where the woman was killed were shattered.
EARLIER: A van has rammed into two bus stops in Marseille, killing one person and injuring another, according to French media reports.
Police tweeted that an operation was under way and asked residents to avoid part of the Old Port area in France's second-largest city.
The 35 year-old male driver was arrested, according to regional newspaper La Provence and BFM-TV. BFM said a witness noted the licence plate of the van and was able to give it to police.
A woman was killed at the second bus stop and a man injured at the first, BFM-TV said. They were in different areas of the city.
A motive for the attacks is not yet known.
The incident comes just days after back-to-back van attacks in Barcelona and the Spanish resort town of Cambrils killed 14 people.
A Marseille police official said it is too early to blame the incident on terrorism, but "given the times" it cannot be excluded as a motive.
David-Olivier Reverdy of the Alliance police union said all possibilities are currently being studied.