Khamzat Azimov was born in Chechnya in 1997 and granted French citizenship after his mother obtained it in 2010. He grew up in a district with a large Chechen community in the eastern French city of Strasbourg. His parents have been taken into custody and one of his friends was arrested in Strasbourg on Sunday afternoon. A soldier killed him after a colleague failed to pacify him with a taser during his rampage on Saturday night.
He was placed on the S list of people judged a potential threat to security and the FSPRT, a list of people believed to be potential terrorists, in 2016. There are reported to be about 20,000 people on both lists and they are subject to varying degrees of surveillance, according to the danger the authorities believe they pose. Azimov was judged suspect because of the company he kept, rather than his own behaviour, sources say. He was interrogated last year by anti-terror police because he knew an associate of someone who had gone to Syria. He had no criminal record.
The Islamic State (IS) armed group has claimed responsibility for the attack, saying it was a "reprisal" for France's participation in the US-led anti-IS coalition, although it offered no proof that Azimov was in touch with it.
Chechnya is a Muslim-majority republic that is part of the Russian federation. Along with other parts of the Caucasus, it was conquered by Tsarist Russia in the mid-19th century, becoming an autonomous soviet republic after the 1917 Russian revolution. There was guerrilla resistance to Russian occupation. The Chechen population, along with the Ingush, was deported in 1944 on the grounds that they were supposed to be German sympathisers and not allowed to return until destalinisation in 1956. Chechnya declared independence in 1991 following the collapse of the Soviet Union and Russia fought two wars to regain control, finally pulling out most of its army in 2009. Current Chechen President Ramzan Kadyrov is a former separatist militia leader who is now an ally of Russian President Vladimir Putin. His government is accused of corruption, brutal treatment of opponents and persecution of gay people. Chechens and other people from the region often face discrimination and prejudice in Russia.
Armed Islamists from the north Caucasus have launched a number of attacks against Russian targets, most notoriously the Beslan school siege, in which 331 people died, and a Moscow theatre hostage-taking, in which 125 people were killed. IS claimed responsibility for a shooting in an Orthodox church in Dagestan in which five women were killed. Russian secret service chief Alexander Bortnikov said last year that at least 4,500 Russians, many from the Caucasus and central Asia, had gone to fight with "terrorists" in the Middle East, north Africa and elsewhere.
Chechen Information Minister Dzhambulat Umarov on Sunday played down the link between the region and the Paris attack, saying that such crimes know "no nationality, no faith, no motherland and no flag". Russian Senator Konstantin Kosachev, who chairs the committee for international affairs, said the attack proved the need to tackle terrorism at its source. "The lines of defence from this global threat must be drawn where it is conceived, financed and encouraged," he said. One of the reasons Russia gave for intervening to support Basher al-Assad in Syria was the need to target Russian jihadists fighting there.
In France the attack was condemned by Hassen Chalghoumi, head of the Conference of French Imams. "Last night's attack reminds us how much our security, freedom and democracy have become targets for these people," he said in a statement. Right-wing politicians have criticised President Emmanuel Macron's government. "In the war against terrorism, words aren't enough, we need action," tweeted Laurent Wauquiez, head of the Republicans party. National Front leader Marine Le Pen demanded to know "Thanks to which network are this Islamist terrorist and his family present on our territory?"
The French government hit back, spokesman Benjamin Griveaux pointing out that "Unfortunately there is no zero risk and those who explain that measures pulled out of a hat will solve the problem are lying." In the last 15 months, 22 attacks have been prevented, he said. The state of emergency imposed after the 2015 Paris attacks was lifted in October when a tough new anti-terror law was introduced. Thousands of troops patrol France's streets as part of the Sentinelle anti-terror operation.
The man who stabbed five people, killing one, in Paris on Saturday night was a French national of Chechen origin who was on France's anti-terror watchlist, it emerged on Sunday. Here's what we know about him and his background so far, as well as some of the reactions to the attack.