A car loaded with gas canisters rammed into a police van on the Champs-Elysees avenue in Paris on Monday, leaving the driver dead in what the interior minister said was an "attempted attack".
Police sources told AFP that a Kalashnikov rifle, handguns and gas bottles were found in the white Renault Megane.
"Security forces have been targeted in France once again," Interior Minister Gerard Collomb said, calling the incident an "attempted attack".
The weapons and explosives found in the vehicle "could potentially blow this car up," he added.
Interior ministry spokesman Pierre-Henry Brandet said bomb disposal experts were on the scene to "ensure the vehicle poses no further danger."
Video showed orange smoke pouring from the car after the impact.
No police or bystanders were injured in the incident near the Grand Palais exhibition hall.
"People were running every which way," said a 51-year-old bystander who gave his name only as Alexandre. "Some shouted at me to get away."
Anti-terrorism prosecutors have opened an investigation.
Police have closed two of the Metro stations on the Champs-Elysees, a world-renowned avenue lined with shops and cinemas that is a major tourist draw in the French capital.
The incident came just two months after a policeman was shot and killed on the avenue, three days before the first round of France's presidential election.
A note praising the Islamic State group was found next to the body of the gunman, Karim Cheurfi, in that incident.
Police later found other weapons in Cheurfi's car including a shotgun and knives.
On June 7, a hammer-wielding Algerian man was shot and wounded by police after he struck an officer on the head in front of Notre Dame cathedral in Paris, shouting it was in revenge "for Syria".
He had pledged allegiance to the Islamic State group in a video found at his home.
String of attacks
The attack on Monday was the latest of a string in Paris and London.
Earlier Monday, a van ploughed into a crowd of Muslims near a London mosque, leaving one person dead and injuring 10 others.
It was the second terror attack this month in the British capital.
Two weeks ago jihadists used a van and knives to crush and stab to death eight people enjoying a night out in the British capital. Three of the victims were French.
France has been consistently targeted by jihadists and remains under a state of emergency imposed after the November 2015 attacks in Paris, when Islamic State jihadists killed 130 people in a night of carnage at venues across the city.
Previous major attacks targeted the Charlie Hebdo
satirical magazine in January 2015.
In July last year, a radicalised Tunisian man killed down 86 people as he rammed a truck through a crowd watching Bastille Day fireworks in the Riviera city of Nice.Last updated: June 19 2017 07:34 PM