UK & World News
Syria Spy Flights Aim To Root Out IS 'Cancer'
Barack Obama has vowed that "justice will be done" against the killers of James Foley, as the US launched surveillance flights over Syria to identify targets for possible airstrikes.
Islamic State (IS) militants, who beheaded the journalist in a video released earlier this month, have seized large parts of the country and neighbouring Iraq - where the US is already conducting airstrikes.
President Obama said he would do whatever is necessary to go after those who harm Americans, and called IS, also known as ISIS or ISIL, a "cancer".
"America does not forget," President Obama told veterans at an American Legion convention in Charlotte, North Carolina.
"Our reach is long. We are patient. Justice will be done."
"Rooting out a cancer like ISIL won't be easy and it won't be quick," he added.
Syria, which is in the throes of a three-year civil war, has warned Washington it would need permission to operate in its airspace.
But White House spokesman Josh Earnest said the US did not even recognise Syria's president, Bashar al Assad, as the country's legitimate leader.
He dismissed an offer from Damascus for a joint effort to combat IS.
State Department spokeswoman Jen Psaki said that when it came to defending US interests, "we're not going to ask for permission from the Syrian regime".
A spokesman for General Martin Dempsey, chairman of the Joint Chiefs of Staff, confirmed on Monday that options for dealing with IS were under review.
He added that Gen Dempsey was working with US Central Command, which is responsible for US forces in the region, to prepare options in both Iraq and Syria "with a variety of military tools including airstrikes".
The Associated Press news agency reported that the surveillance flights got under way on Tuesday.
The US ran surveillance missions over Syria ahead of an attempted mission to rescue Mr Foley and other US hostages this summer.
That mission failed, possibly due to imprecise intelligence, as the hostages had already been transferred by the time the special forces launched the raid.
IS is also threatening to kill Steven Sotloff, another American journalist, and other US citizens held captive in Syria.