the rundown Brussels neighbourhood of Molenbeek, which has a reputation as a hotbed of Islamic militancy and where police have made several arrests.

Abdelhamid Abaaoud, 28, a Belgian of Moroccan descent also from Molenbeek and thought to be fighting for IS in Syria, is considered a possible mastermind of the attacks.

Five of seven known attackers have been identified, but it is unclear if other gunmen fled after the carnage.

Two of the gunmen behind the bloodbath at the Bataclan, where 89 people were killed, have been identified as 29-year-old Paris native Omar Ismail Mostefai and 28-year-old Samy Amimour. Both detonated suicide bombs.

A Turkish official said its police had twice warned France about Mostefai, who was one of 10,000 people tagged by French intelligence as an extremist.

Amimour was charged in Francein 2012 for "conspiracy to commit terrorism" over an attempt to travel to Yemen and was wanted on a global arrest warrant after violating the terms of his judicial supervision.

There are fears some of the assailants entered Europe as part of the huge influx of people fleeing Syria's civil war, after a Syrian passport was found near the body of one suicide bomber at the Stade de France in the name of Ahmad Al Mohammad.

The document has yet to be verified and Serbia detained a migrant on Monday whose passport contained the same data.

The attacks came less than 11 months after jihadists struck the Paris offices of satirical magazine Charlie Hebdo and a Jewish supermarket, killing 17.