As early as last year Abdelhamid Abaaoud was already known to security forces after appearing, laughing, in an Islamic State video.
The Islamic State jihadist suspected of orchestrating the Paris attacks was killed in a major police raid in the French capital, prosecutors confirmed on Thursday, raising troubling questions about a breakdown in intelligence and European border security.
Abdelhamid Abaaoud, a Belgian of Moroccan origin linked to a series of extremist plots in Europe over the past two years, died in Wednesday's assault by elite police units on an apartment in northern Paris.
The 28-year-old was thought to have been in Syria -- where he had boasted of planning attacks on the West -- and his presence in France will renew debate about Europe's border controls and monitoring of fighters returning from Syria.
Confirmation that such a high-profile figure from the Islamic State (IS) group had managed to slip undetected into France prompted a sharp response from Interior Minister Bernard Cazeneuve, who demanded Europe step up its response to the terror threat.
He said Paris had received "no information" from other European countries about his arrival on the continent.
"It is urgent that Europe wakes up, organises itself and defends itself against the terrorist threat," Cazeneuve told reporters.
Abaaoud was the subject of an international arrest warrant issued by Belgium -- where a court had in July sentenced him in absentia to 20 years in prison for recruiting jihadists for Syria.
But it was only three days after the Paris bloodbath that "intelligence services of a country outside Europe indicated they had knowledge of his presence in Greece," Cazeneuve said, without specifying which country.
Abaaoud was also checked by police at Cologne-Bonn airport on his way to Istanbul in early 2014, German officials said, but was allowed to go as they had no indication he should be stopped.
Radical CousinEU interior and justice ministers are to meet in Brussels on Friday where they will tighten checks on all travellers at the external borders of the passport-free Schengen zone as an emergency measure.
French Prime Minister Manuel Valls said the bloc's cherished policy of passport-free travel in the so-called Schengen zone would be "called into question" if Europe "doesn't live up to its responsibilities."
Abaaoud was involved in four out of six attack plots foiled in France this year, Cazeneuve said, including one to attack a church near Paris. Police are also probing links to a thwarted assault on a high-speed train from Amsterdam to Paris in August.
As the Paris probe widened to countries across Europe, Belgian police arrested nine people in Brussels, seven in raids linked to a suicide bomber who blew himself up outside the French national stadium in Paris last Friday.
Italy was also hunting five suspects after an FBI tip-off about possible jihadist attacks on landmark sites.
Paris prosecutor Francois Molins said handprint analysis was used to identify Abaaoud's body, found riddled with bullets in the rubble of the shattered building in Saint-Denis following a seven-hour police siege.
Molins said it was not yet clear whether Abaaoud blew himself up. Another body found after the ferocious shootout is thought to be that of Abaaoud's 26-year-old cousin Hasna Ait Boulahcen, who detonated an explosives vest.
Fresh raids were launched on Thursday on a house northeast of Paris where Boulahcen lived until recently with her mother and siblings.
Her brother said she had become radicalised about six months ago and began wearing a full face veil or niqab.
"She was unstable, she wasn't looking to study religion, I have never seen her open a Koran," he told AFP, saying she had left home three weeks ago.
Suspect unaccounted forEight arrests were made in Wednesday's massive raid in Saint Denis, but another key suspect, Salah Abdeslam, remains unaccounted for.
Abdeslam is thought to be one of the only surviving members of the group of assailants behind the Paris attacks. His suicide-bomber brother Brahim Abdeslam blew himself up at a cafe without killing anyone.
Chilling CCTV footage has emerged in which a gunman can be seen pointing his weapon at a woman crouching under a table outside the cafe -- but it jams, allowing her to flee.
A video has also emerged from the bloody scene outside La Bonne Biere restaurant just seconds after it came under fire, with bodies seen lying on the ground as people rushed to help the victims. "It's carnage", a voice can be heard saying off-camera.
Also on Thursday, French lawmakers voted to extend an extraordinary package of security measures for three months as Valls warned of "the risk from chemical or biological weapons."
The measures include allowing police to carry weapons when they are off duty and use them in the event of an attack. French MPs also voted to let the government block websites and social media accounts promoting or inciting terrorist acts.
Meanwhile French President Francois Hollande ordered French air strikes against Islamic State (IS) jihadists be stepped up in Iraq as well as Syria, his office said.
At least 129 people were killed in the shootings and suicide bombings that targeted a concert hall, bars and restaurants and the Stade de France national stadium on Friday.
It was the second major attack in Paris in less than a year. In January, jihadist gunmen killed 17 people at Charlie Hebdo satirical magazine, on the streets and in a Jewish supermarket.