One person was killed and at least four others were injured in a shooting west of Paris, French Prime Minister Sebastien Lecornu said on Friday.
A suspect has been arrested. Firefighters were called to a petrol station where the shooting occurred.
Ali Rabeh, the mayor of the Yvelines town of Trappes, told BFMTV that a man had fired shots from his car and "appeared to be firing at random and seemed intent on carrying out a massacre".
He said one of those injured was a 12-year-old girl, adding that the shooter lived in a near-by town. There was no information so far about his motives, he said.
Mr Lecornu wrote on X that security forces had been fully mobilised. "The national anti-terrorism prosecutor’s office has announced that it is monitoring the situation," he added.
Representatives for the prosecutor's office did not immediately respond to a request for comment, and the prefecture declined to comment. The anti-terrorism prosecutor's office confirmed it was monitoring the case.