THE head of the Russian republic of Chechnya says France bears responsibility for the fatal knife attack by a Chechnya-born man in Paris.

Chechen President Ramzan Kadyrov said overnight that he has been informed the dead attacker had received French citizenship and held a Russian passport until he was 14.

A French judicial official not authorised to speak publicly says the suspect was born in November 1997, which would have made him 20 now.

Mr Kadyrov identified the suspect, whom police fatally shot, as Khasan Azimov; French media reports gave his first name as Khamzat.

Russian news agencies quoted the Chechen leader saying: “I consider it necessary to state that all responsibility for the fact that Khasan Azimov went on the road of crime lies completely with the authorities of France.

“He was only born in Chechnya, and his growing up, the formation of his personality, his views and persuasions occurred in French society.”

On Sunday, police arrested a friend of the attacker in the eastern city of Strasbourg, an official source has said.

The man, who is being held for questioning, was also born in 1997 — the same year as the attacker — the source added.

The friend is the third person French police have taken in for questioning since the suspect in the attack killed one person and wounded four others.

The parents of the alleged attacker were picked up in the northern 18th district of Paris after their son was fatally shot by police.

A French official said the alleged attacker had been on police radar for radicalism.

The judicial official told The Associated Press that while the alleged assailant had no record of arrests or convictions, he had been on a nationwide database of thousands of people suspected of links to radicalism.

The official wasn’t authorised to be publicly named speaking about an ongoing investigation. The assailant was killed by police after fatally stabbing one man and injuring four other people. The attacker’s parents are under questioning. Counter-terrorism investigators are leading the probe into Saturday’s attack near the Paris opera house, which was claimed by the Islamic State group.

Authorities say the attacker was born in the majority Muslim Russian republic of Chechnya, which has long grappled with extremism. The Russian Embassy in France wouldn’t comment on Sunday.

A 29-year-old man was killed in the attack and four people were wounded. Interior Minister Gerard Collomb said one of the injured underwent emergency surgery, and two friends were hospitalised with less serious injuries, but all are out of life-threatening danger.

The attacker was killed by police after the stabbing near the Opera Garnier on a busy Saturday night.