Four jets left in pairs within about an hour of each other from the airbase.
Facebook message warns Younes Abaaoud, 15, is on his way back from Syria to revenge his 'martyr' brother.
Activist group announces 'Day of Rage' demonstrations against jihadists on 11 December.
Tensions between the two nations show no signs of easing since Turkey shot down a Russian warplane.
Announcement comes after US deploys more special forces to the country.
Islamic State has easily tapped into Saddam-era smuggling networks.
The Labour leader has attacked the Prime Minister over plans for air strikes in Syria.
Kingdom's UK ambassador calls such accusations an 'insult'.
UK MPs are debating whether to join the US and France in carrying out air strikes on Isis targets in Syria.
Nato defence spending has been steadily cut back since 2009 - but that is about to change.
The UK Prime Minister has opened a mammoth debate on what action to take in Syria against Islamic State.
David Cameron has urged Britons to refer to Islamic State by its Arabic acronym, Daesh.
Labour leader warned more civilians could be killed if the RAF is ordered to bomb Syria.
The SNP firebrand urged the prime minister to apologise for the 'deeply insulting' comments.
Cameroon has been facing almost daily suicide attacks from the Nigerian terror goup Boko Haram.
MPs locked in crucial 10-hour debate to decide whether to back air strikes against Islamic State in Syria.
Terror group wants to include African nation under an expanded 'caliphate' besides using it for operations.
Nicholas Michael Teausant had also spoken of wanting to bomb the Los Angeles subway system.
Strategy shift follows perceived Isis aim to cause maximum casualties.
Support for airstrikes fall from 59% to 48% after Cameron set out his case in Parliament last week.
Downing Street's proposal to bomb Syria lacks substance, Labour leader says.
Only 56 people have been arrested in the US on terrorism-related charges in 2015.