"As of 9 September, 30,542 people have been displaced from northwest Syria, moving to different areas across Idlib", David Swanson, spokesman for the UN Office for the Coordination of Humanitarian Affairs (UNOCHA) said.
United Nations regional coordinator for Syria Panos Moumtzis on Tuesday voiced concern over an uptick in air strikes and shelling that has sent more than 30,000 people fleeing, mainly to locations within the contested province of Idlib.
Idlib and nearby areas are largely controlled by Hayat Tahrir al-Sham, an alliance led by Al-Qaeda's former Syrian affiliate, as well as rival rebels.
"Getting smuggled across is nearly impossible, and there have been several cases of displaced people being shot dead while trying to enter Turkey illegally", Rifai said.
Ankara, which hosts some 3.5 million refugees, has said it could not take any more if an attack on Idlib drove a new surge of people toward its border.
The Russian defence ministry, citing Idlib residents, said film crews from several Middle Eastern TV channels as well as "a regional branch of a leading USA news channel" had arrived for the shoot in the city of Jisr al-Shughur in Idlib.
The attack, which came in response to what the USA and its allies insisted was another chemical attack in Douma, on the outskirts of Damascus, saw 105 cruise missiles being fired from sea and air at Syrian government targets.
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The garrison has served as a launchpad for U.S. counter-Islamic State operations and a U.S. Special Operations Forces training facility for Syrian fighters aiding in that effort.
"Idlib province is ... a sort of zone of responsibility of Turkey; it is their responsibility to separate the moderate opposition from the extremists, from Jabhat al-Nusra and other groups, other terrorist groups", he said. "In order to eliminate terrorist and extremist elements in Idlib and to bring to justice foreign fighters, a more comprehensive worldwide counterterrorism operation is necessary", he said.
Turkish President Recep Tayyip Erdogan on Tuesday called on Russian Federation and Iran to halt a looming "humanitarian disaster" in Idlib, saying Syrians there could not be left to the mercy of President Bashar al-Assad.
The intense air raids came a day after Iran and Russian Federation backed a military campaign in the rebel-held area despite Turkey's pleas for a ceasefire.
Syria has been ravaged since 2011 by a complex civil war, implicating many foreign powers, that has claimed more than 350,000 lives to date. "The safety and protection of some 2.9 million civilians residing in Idlib and surrounding areas is at risk", said Moumtzis.
At least two hospitals and two centers running rescue operations for wounded people were put out of service by shelling and air strikes, according to the Britain-based Observatory and the Union of Medical Care and Relief Organisations, which backs medical centers in Syria.
De Mistura met informally with members of the three delegations on Monday.
The Trump administration has warned for days about an expected assault on Idlib, the last major stronghold for rebels fighting in Syria, while urging Syrian leader Bashar Assad and his allies not to use chemical weapons.
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