One person has been killed and at least four others wounded in a gun attack in a Parisian suburb, which police have said they are treating as a terrorist incident.

French Prime Minister Sébastien Lecornu said the "very serious events" happened in Trappes, to the southwest of Paris, adding that the suspected attacker had been "apprehended and placed in police custody".

The National Anti-Terrorist Prosecutor's Office (PNAT) said it had taken on the investigation into the incident, which appeared to be "murder in connection with a terrorist enterprise".

Reports in French media suggest the number of injured may be higher and that a 12-year-old child may be among them.

The mayor of Trappes, Ali Rabeh, said that "an individual fired shots from his vehicle at several people he encountered" on Friday morning.

The alleged gunman "wandered aimlessly" through several neighbourhoods and "fired randomly" with the seeming intent of causing "as many casualties as possible", Rabeh told BFMTV.

"He wanted to cause carnage," he said.

The attacker reportedly travelled down a main road, shooting intermittently out of his car window.

A local police chief told BFMTV that the suspect had used "an older-style semi-automatic weapon" with bursts of fire. Le Parisien reports that the gun dated back to World War Two.

Rabeh said the shooter had hit a health centre, a petrol station and several vehicles during the spree.

The suspected attacker was then arrested at the nearby town of Coignières, local media report.

French Interior Minister Laurent Nuñez said en route to Trappes that the incident "looks like a murderous rampage" but that the motive of the attacker remained unclear.

The suspect, a 39-year-old, was known to police but not to France's intelligence services, local media report.

Rabeh suggested that the African heritage of two of the victims of the shooting may indicate a motive.

PNAT said their investigation also includes "possession of a Category A weapon" - which includes military-grade weapons or weapons capable of firing in bursts.

The anti-terrorist office also said their investigation is looking into "conspiracy with a terrorist group for the purpose of preparing crimes against persons".

French President Emmanuel Macron shared his "deep emotion" and thoughts for the victims, adding: "In this terrible ordeal, the nation stands by their side."