"Abdelhamid Abaaoud - and others involved in the Paris attacks - exploited the chaos of Europe's migrant crisis to come and go as they pleased by posing as refugees"
“........Intelligence failures appear to have allowed Abaaoud to act with impunity. He had travelled to Syria in 2013, then returned to Belgium via Greece. He was able to leave Belgium undetected and return to Syria, a round trip he made several other times, he says.
He was related to Ibrahim Abdeslam, one of the suicide bombers in Friday’s attack, and in 2010 spent time in jail with Abdeslam’s brother Salah, currently Europe’s most wanted man after going on the run after the attacks. They were childhood friends, having grown up in the same Molenbeek district of Brussels as several of the other suspects. http://www.telegraph.co.uk/news/worldnews/europe/france/11997410/Paris-attackers-linked-to-Belgian-suburb-where-the-authorities-have-lost-control.html
Abaaoud’s family had previously been told that he was dead, but it appears to have been an Isil ruse to throw police off his scent.......”