An international manhunt is under way for one of the suspects in the Paris terrorist attacks after it emerged that French police let him slip through their fingers in the hours after the atrocity.
Salah Abdeslam, whose brother Ibrahim was one of seven Isil suicide bombers in Friday's massacre, was in a car stopped by police in Cambrai, near the Belgian border on Saturday, but was allowed to proceed after nothing suspicious was found.
It was only later, when a VW Polo used by the terrorists was linked to him, that police realised their mistake.
Last night Abdeslam, 26, became Europe's most wanted man after France issued an international arrest warrant for him, warning the public "absolutely" not to approach him. A third brother, Mohammed, was one of seven alleged plotters arrested in Belgium.
The Belgian security services believe a total of 20 people may have been involved in the plot, meaning five others besides Abdeslam are on the run.
In other developments:
u?France responded as 10 fighter jets dropped 20 bombs on targets in the Isil-stronghold of Raqqa in Syria, the French Defence Ministry said.
u?A new security crackdown will mean holidaymakers heading for the UK facing car boot searches and Border Force interceptor ships will patrol the shorelines to prevent entry by jihadists.
u?David Cameron indicated he still wants to extend air strikes into Syria as he began a coordinated diplomatic attempt with Barack Obama to persuade Vladimir Putin to back their efforts to destroy Isil.
u?Thousands of British troops are on standby to take to the streets in the event of a Paris-style terror attack.
u?An extra 2,000 spies are to be recruited at MI5, MI6 and GCHQ in the largest expansion of the security and intelligence services since the 7/7 attacks a decade ago.
u?A fake Syrian passport used by one of the bombers suggests the migrant crisis is being exploited to enable terrorists to travel through Europe.
As efforts to identify all 132 victims of the terrorist attacks continued, the Foreign Office indicated only one British man - 36-year-old Nick Alexander, who was working at the Bataclan concert hall - is among the dead. The hunt for remaining members of the terrorist cell focused on Belgium, where at least three French nationals believed to be involved in the plot were living.
French police admitted that Salah Abdeslam, one of three brothers allegedly at the centre of the cell, could have been held by them as he and two alleged accomplices headed for the Belgian border on Saturday morning. Their grey VW Golf was stopped by police in Cambrai, but nothing suspicious found and after their names had been taken they were allowed to continue.
Later in the day, police discovered that a Belgian-registered VW Polo found abandoned near the Bataclan, and identified as being used by the terrorists, had been rented by Abdeslam, and it was only then that they realised he had been within their grasp.
A spokesman for the Paris prosecutor's office said: "A person who rented a vehicle implicated in the attacks was subject to a road check in Cambrai [northern France] on Saturday at 9.10am on the A2 motorway to Belgium." The car was later seized at Molenbeek-Saint-Jean, a suburb of Brussels, on Saturday afternoon.
A Seat Leon car found with Kalashnikov rifles inside had been rented by his brother Ibrahim, who blew himself up at the Comptoir Voltaire restaurant on Friday night, severely injuring one person.
Tim Ramadan, who works with the Syria-based group "Raqqa is Being Slaughtered Silently", said that earlier this year he overheard foreign fighters plotting a "huge" terror attack in Paris from an internet cafe in Raqqa. He said the man he overheard used the nom-de-guerre Abu Ibrahim al-Belgi - "father of Ibrahim, from Belgium" - and was speaking to a "commander" who gave the orders for an attack.
Another of the suicide bombers, who blew himself up during the attack on the Bataclan theatre, has been named as Ismael Omar Mostefai, 29, a French national who is believed to have travelled to Syria to an Isil terrorist training camp before returning.
He was identified by DNA recovered from the concert hall, which matched samples held on file from petty crimes. He had been identified as a potential security threat in 2010 after being radicalised in Chartres by a Belgian imam. The Syrian passport found near one of the bombers at the Stade de France bore the name Ahmad Almohammad, and police are working to establish if that was the real name of a bomber. It was used to enter Greece and to claim asylum in Serbia in October.
British security services are working closely with their French and Belgian counterparts to round up any remaining members of the Isil terrorist cell. A Downing Street spokesman said the Foreign and Commonwealth Office sent a rapid response team to Paris immediately after the attacks and is offer consular support in Paris and the UK.