Tens of thousands of Syrian refugees have streamed over the Iraqi border since Thursday, fleeing internecine fighting between local Kurdish authorities, the Free Syrian Army and al-Qaeda affiliates as they all vie for control of the strategic corridor in northeastern Syria.
On Monday, 3,000 Syrians crossed the border in what has been a total exodus of 30,000 in five days, one of the biggest such movements since the country's conflict began. Iraqi officials and the UN are warning of a looming humanitarian crisis.
"If the numbers of refugees continues to rise and surpasses 250,000, then the government and aid agencies won't be able to provide for them and the effect will be catastrophic," said Atta Mohamed, regional director for the Civil Development Organization, an Iraqi humanitarian organization working with the UN refugee agency, UNHCR.
Since the Syrian uprising began in March, 2011, 1.9 million have fled the country, mainly to escape bombardment or persecution by the regime, according to the UN.
But what makes the situation in the northern region of Syria unique is that refugees are fleeing a secondary set of conflicts that have arisen after regime forces mostly pulled out of the predominantly Kurdish area a few months ago. Since then, Kurdish militias that back the regime have fought with the Free Syrian Army (FSA) for control of these strategic areas and both groups have battled al-Qaeda-affiliated groups for control of the Iraqi corridor, a lifeline for fighters, weapons and supplies.
The UN has sent 70 trucks carrying aid into Iraqi Kurdistan to deal with the refugee influx. Those who crossed into Iraq last week had been camped at the border for several days and were "completely exhausted and in the most precarious position," said Peter Kessler, a UNHCR spokesman. "They are frightened, they are worried, they are nervous."
Refugees say the situation in northern Syria has become untenable.
"We came here because of the fighting from al-Nusra," said Kerema Sulaiman said, referring to a rebel front linked to al-Qaeda. She spoke as her family of six lay together on a carpet and sipped tea brought to them by local soldiers guarding the makeshift camp in a Sulaymaniyah school they now call home. "Slowly, slowly war has been coming to Derek," she said about her Syrian town.
Iraqi Kurdish officials are concerned. Last week, Massoud Barzani, the President of the autonomous Iraqi Kurdish region, warned that he would use "all capabilities to defend the Kurdish women, children and citizens in [Syrian] Kurdistan" in response to the escalating violence in the region he blames on extremist groups operating there such as al-Nusra and the Islamic State in Iraq and Sham (ISIS), an umbrella group of domestic and foreign extremists that al-Qaeda has described as its branch in Syria.
These groups, better equipped and more organized, have been winning against the FSA and Kurdish militias in the northern region, local activists say.
For example, in the Syrian province of A-Raqqa, ISIS has solidified its control of its capital city of the same name by attacking its former allies in the city – the FSA – and capturing its soldiers.
As it has done so, ISIS has been imposing what local activists describe as "reckless" Islamic sharia law, arresting civilians who violate their rules and taking hundreds of locals prisoners. They have destroyed alcohol stocks, publicly flogged sharia violators, and enforced modest dress requirements for women. These days, black al-Qaeda flags fly over the city and Islamist declarations mark city walls.
These groups have long-term ambitions for post-Assad Syria, analysts say.
"ISIS's aspiration is to establish an Islamic state in Iraq and the greater Levant, as a prelude to establishing a transnational Islamic Caliphate," said Aymann Jawad al-Tamimi, a fellow at the conservative Washington-based think tank Middle East Forum.
Meanwhile, protests against the ISIS are in their third week in A-Raqqa and demonstrators are demanding the release of hundreds of prisoners they say ISIS fighters arbitrarily arrested. Protesters are also calling for the expulsion of the extremist group from their city and hoping they won't be forced to flee to Iraq.
"We fell under the control of these groups that entered the city in their black outfits, masked and heavily armed with weapons," said Fatima Hussein, a Kurdish 23-year-old student.
"Did we rid ourselves of the injustice of the regime only for a new power to conquer us?"