Suspect arrested after car rams Paris anti-terrorism troops

French police shot and arrested a suspect in a dramatic motorway chase on Wednesday after a car smashed into soldiers outside a barracks in a Paris suburb, injuring six.

The suspected terror attack follows a string of assaults that have hit France since January 2015, claiming more than 230 lives.

The suspect, a 36-year-old Algerian man, was hospitalised after police shot him five times.

The servicemen were hit by a BMW that drove down a quiet street in the upmarket western Paris suburb of Levallois-Perret about 8am local time.

It accelerated as it neared the troops, rammed into them and then sped away. Three were shocked and lightly hurt, while the other three sustained more serious injuries that are not life-threatening, officials said.

"I heard a huge crash that I thought was the sound of scaffolding being put up," said Thierry Chappe, an AFP employee who lives in a building opposite the scene.

About 300 police officers later tracked the rented vehicle to a motorway near the northern port of Calais.

After a chase, officers opened fire, wounding the unarmed driver who was arrested and then taken to hospital, sources involved in the manhunt said.

The suspect lived in the Yvelines suburb of Paris and had no previous convictions.

Pictures showed the black BMW with a crumpled front end and smashed windscreen on the A16 motorway.

The servicemen targeted in the assault were part of the 7,000-strong anti-terrorism Sentinelle force set up in January 2015, after gunmen attacked the offices of satirical weekly Charlie Hebdo, killing 12.

The armed, uniformed soldiers of the force patrol the streets and guard high-risk areas such as tourist sites and religious buildings.

President Emmanuel Macron congratulated security forces on Twitter for apprehending the suspect, adding: "Vigilance remains a duty at all times."

Interior Minister Gerard Collomb said Sentinelle forces had been attacked on six occasions since 2015. France has been under a state of emergency since the Islamic State (IS) group attacks in Paris in November 2015, which left 130 people dead.

Some experts believe patrols should be withdrawn from the streets where they are an obvious target for extremists, but the government is hesitant to do so in case of another major attack.

"The opposition would jump on the argument that, 'You've dismantled Sentinelle, there's been an attack and you are to blame'," said Alain Rodier, a specialist from private national security organisation Cf2R.

The Paris prosecutors' office said its anti-terrorism unit has launched a probe into "attempted killings... in relation to a terrorist undertaking".