Prosecutors in France say the suspected ringleader of the Paris attacks, Abdelhamid Abaaoud, has been listed among those killed in a French police raid on Wednesday.
Abdelhamid Abaaoud, the Islamic State (IS) militant had died in a flat in the Paris suburb of Saint Denis. His body was found riddled with bullets and shrapnel in the apartment.
Interior Minister Bernard Cazeneuve said he had received intelligence that Abaaoud had passed through Greece on his return from Syria. It is unclear whether the Belgian had concealed himself among the thousands of migrants arriving in Greece before heading for other EU nations.
Friday's gun and suicide bomb attacks in the French capital left 129 people dead and hundreds injured.
One of the other attackers, who blew himself up outside the Stade de France, was traced to Greece by his fingerprints, where he was registered as a migrant.
In other developments, France presented a draft resolution at the UN calling for global support in the fight against IS. Nine people were arrested in Belgium after searches linked to the Paris attacks
New searches were also carried out in France
French President Francois Hollande has ordered an "intensification" of air strikes on IS targets in Iraq as well as Syria but the French Prime Minister Manuel Valls warned that France could face chemical or biological attack from terror groups.
The French Parliament has extended the state of emergency for a further three months from 26 November. Confirming Abaaoud left for Syria last year, Mr Cazeneuve said no EU states had signalled his return.
The minister also implicated Abaaoud in four out of six attacks foiled in France since this spring. He was linked to a plot in April to attack a church near Paris. Police are also investigating a possible connection to the attack on a high-speed train from Amsterdam to Paris in August.
In Belgium, he had links to an Islamist cell that was broken up in a raid by security forces in the town of Verviers in January which led to the deaths of two gunmen.
Police sources told AFP news agency that the tip-off about Abaaoud's presence in Greece had come from Moroccan intelligence. Eight people were arrested and at least two killed in the raid on the property in Saint Denis. Heavily armed police stormed the building after a tip-off that Abaaoud was in Paris.
A woman at the flat - reported in French media to be Abaaoud's cousin - died during the raid after activating a suicide vest.The prosecutor's office said it was still unclear whether Abaaoud had blown himself up or not. The 28-year-old was identified from his fingerprints.
Mr Cazeneuve told reporters that a non-EU state had alerted France on Monday that Abaaoud had been in Greece.