Police watched the suspected mastermind of the Paris attacks being led by a woman into an apartment the evening before both died there in a raid by special forces, a police source said on Friday.
After a tip-off from Morocco that Abdelhamid Abaaoud, one of Islamic State's most high-profile European recruits, was in France, police honed in on Hasna Aitboulahcen, a woman already under surveillance who was known to have links to him.
Police tapping her phone as part of a drugs investigation tracked her to the St. Denis suburb north of Paris, also home to the stadium where three suicide bombers blew themselves up during last Friday's attacks that killed 130 people.
They watched the 26-year-old woman take Abaaoud into the St. Denis building on Tuesday evening. In the early hours of Wednesday, police launched an assault that lasted seven hours.
Abaaoud, 28, and Aitboulahcen, who may be his cousin, both died during the gun battle during which French police commandos fired more than 5,000 shots. A third person, who has yet to be identified, died with them.
Officials initially said Aitboulahcen had blown herself up, becoming Europe's first female suicide bomber, but a source close to the investigation said on Friday that a head blasted into the street by an explosive vest was not hers.
One of the police sources also said Abaaoud had been caught on camera at a suburban metro station, after the shootings and at cafes and restaurants in central Paris but while a massacre in the Bataclan concert hall was still underway.
He was seen on closed circuit TV at the Croix de Chavaux station in Montreuil, not far from where one of the cars used in the attacks was found, the source said.
A week after the Paris attacks, French nationals were in the firing line again in Mali when Islamist militants stormed a hotel in the capital Bamako leaving at least 27 people dead although France's defense minister said he was not aware that any French were among those killed.
In response to the Paris attacks, French police carried out raids across the country for a fifth day overnight on Thursday.
So far, police have searched 793 premises, held 90 people for questioning, put 164 under house arrest and recovered 174 weapons including assault rifles and other guns, the Interior Ministry said on Friday.
Police searched a mosque in Brest in western France early on Friday. Its imam, Rachid Abou Houdeyfa, who has condemned the Paris attacks, achieved notoriety this year for telling children they could be turned into pigs for listening to music.
In an unusual step, the French Council of the Muslim Faith (CFCM) – the main umbrella group for mosque associations – and several of its member groups, urged their imams to denounce the attacks in Friday sermons and distributed suggested texts.
A bill to extend a state of emergency imposed a day after the Paris attacks into February and which would give the police more powers, received a final approval from the upper house of parliament on Friday.
Since the attacks, requests for information about joining the French army have surged. Colonel Herve Chene, head of airforce recruitment, said the numbers of people visiting his unit's hiring centres had tripled since last Friday.
Abaaoud was spotted on the metro station CCTV tape at 10:14 pm (2114 GMT) on Friday last week after the initial wave of attacks. Seven assailants died and a suspected eighth person, Salah Abdeslam, is still on the run.
Abaaoud was a petty criminal who went to fight in Syria in 2013 and European governments thought he was still there until Morocco said he was actually in France.
He is believed to have recruited young men to fight for Islamic State from immigrant families in his native Brussels district of Molenbeek and elsewhere in Belgium and France.
Abaaoud appeared in Islamic State's slick online English-language magazine Dabiq, where he boasted of crossing European borders to stage attacks. He claimed to have escaped a continent-wide manhunt after a police raid in Belgium in January in which two militants died.
Islamic State, which controls parts of Iraq and Syria, has attracted thousands of young Europeans and Abaaoud was seen as a leading figure in luring others, particularly from Belgium.
His own family has disowned him, accusing him of abducting his 13-year-old brother, who was later promoted on the Internet as Islamic State's youngest foreign fighter in Syria.
Moroccan authorities, who have detained scores of Islamic State militants in recent months, also arrested Abaaoud's brother Yassine last month after he arrived in Agadir, a Moroccan security source said on Friday.
Morocco's king is in France and met French President Francois Hollande on Friday.
While quickly tracking Abaaoud down will be seen as a major success for French authorities, his presence in Paris will focus more attention on the difficulty European security services have in monitoring the continent's borders.
Two of the men who blew themselves up outside the Stade de France stadium last Friday travelled together to Greece and had their fingerprints taken there on October 3, the Paris prosecutor said in a statement on Friday.
EU interior and justice ministers in Brussels on Friday pledged solidarity with France in the wake of the attacks and agreed a series of new measures on surveillance, border checks and gun control.
The 28 governments agreed to speed new legislation to share air passengers' data, curb firearms trafficking and ensure closer checks on EU citizens crossing Europe's external borders.
France has called for changes to the EU's Schengen border-free travel zone to make it tougher to travel across Europe. Hundreds of thousands of people have reached Europe as Syrian refugees in recent months, including at least one person using a passport found at the scene of Friday's attacks.
France has called for a global coalition to defeat the group and has launched air strikes on Raqqa, the de-facto Islamic State capital in northern Syria, since the weekend.
Russia has also targeted the city in retribution for the downing of a Russian airliner last month that killed 224.
The attacks in Mali were another slap in the face for France, which has stationed 3,500 troops in northern Mali that are meant to be restoring stability and security after a Tuareg rebellion was hijacked by Al-Qaeda linked fighters in 2012.
"It is the same terrorists under different names who are fighting us and who we are fighting. It will be a long war," French Prime Minister Manuel Valls told reporters.