Turkish Military Strikes Airport in Syria
Ankara has ramped up its attacks against the Syrian forces since Thursday, when 33 Turkish soldiers were killed in an air strike by the Syrian army.
Syria's army warned it would take down any planes or drones breaching the air space over the northwest.
The latest bout of fighting in Idlib has uprooted one million civilians since December, many of them women and children fleeing towards the Turkish border. Turkey, which hosts 3.7 million Syrians, said it would allow migrants to cross into Europe in anticipation of an imminent new migrant influx from Idlib, lifting restraints on movement in place since 2016 under a deal with the European Union.
Greece placed its borders on maximum security footing on Sunday after hundreds of migrants used porous crossing points to enter the country from Turkey, with thousands behind them seeking entry after Ankara's relaxation of policy.
Turkey's borders to Europe were closed to migrants under an accord between the Turkish-EU deal that halted the 2015-16 migration crisis, when more than 1 million people crossed into Europe by foot.