By Suadad al-Salhy and Murad Talaat
BAGHDAD/PESHKHABOUR, Iraq (Reuters) - A sudden mass influx of 30,000 Kurdish refugees from Syria into Iraq increases the likelihood that Iraq's Kurdish region will act to protect its kin across the border, an adviser to Iraqi Kurdish leader Massoud Barzani said on Monday.
The United Nations said nearly 30,000 refugees had crossed in the past few days, making it one of the biggest single outward migrations of a civil war that has killed more than 100,000 people and driven millions from their homes.
"It is a massive movement of people," Dan McNorton, spokesman of the U.N. High Commissioner for Refugees (UNHCR), told Reuters on Monday.
The U.N. agency has sent trucks loaded with emergency supplies and erected plastic tarpaulins at a transit site to provide shelter from the sun and heat. A refugee camp is expected to open by the end of the month, McNorton said.
Refugees who crossed a newly built metal pontoon bridge spanning the Tigris river said they were fleeing attacks by the al-Nusra Front, a radical Sunni Arab rebel group which has merged this year with Iraq's own resurgent branch of al Qaeda.
"There are bodies without heads at the morgue today. Why? Which international norms and which doctrine can justify their death? They are cutting off heads. Heads of children are being cut off," said Faris Sulaiman, a refugee who fled from Qamishli in northeast Syria.
"The al-Nusra Front have permitted the killing, the slaughtering of the Kurdish people," he said.
Barzani, leader of Iraq's autonomous ethnic Kurdish region in the north, floated the idea this month for the first time of intervening across the Syrian border. In a letter posted on his website on August 10 he said he had sent envoys to Syria to investigate reports civilians were being killed.
"If the reports are true, showing that citizens, women and the children of innocent Kurds are under threat from murder and terrorism, Iraq's Kurdistan region will make use of all of its capabilities to defend women and children and innocent civilians," Barzani said in the letter.
A Barzani adviser told Reuters on Monday that the sudden refugee influx increased the likelihood that he would order action, although he played down the suggestion the leader might dispatch his powerful security forces across the frontier.
"Sure, Barzani's intervention has become likely after what has happened in the last few days. But I do not expect that he will involve the military."
"Mr. Barzani has expressed his dissatisfaction with the massacres suffered by the Kurdish people in Syria and asked the U.N., U.S. and neighboring countries to protect the Kurdish people who are facing semi-genocide," the adviser said.
WAR ON BOTH SIDES OF FRONTIER
Syria's civil war has spilled across the Iraqi frontier, with Syria's al-Nusra Front merging this year with Iraq's branch of al Qaeda - the same group that fought for the past decade against U.S. forces and Iraq's Shi'ite-led government.
On the Iraqi side of the border, al Qaeda has claimed responsibility for repeated bombings targeting civilians and the security forces that have brought violence to levels unseen in more than five years, before U.S. troops withdrew in 2011.
In Syria, the opposition to President Bashar al-Assad has splintered on sectarian and ethnic lines after two years of war, with rival rebel groups turning on each other in a scramble for control of territory in the divided country.
In Syria's Kurdish-populated northeast, which Kurds in neighboring countries refer to as "western Kurdistan", Kurds have flown their own flag over towns and villages in an apparent bid to create an autonomous region modeled on the one in Iraq.
Kurds have no state of their own but predominate in parts of Syria, Turkey and Iran as well as Iraq. Iraq's Kurds are the only ones with self-rule, having maintained autonomy since 1991.
Barzani controls thousands of men under arms in a well-organized regional security force known as the Peshmerga, which could have a dramatic impact in Syria were it to cross the frontier. That would be the biggest intervention from a neighboring country since thousands of fighters from Lebanon's Hezbollah Shi'ite militia came to the aid of Assad this year.
Turkey, the regional heavyweight which has been making peace with its own Kurds after decades of insurgency, has been lukewarm to the idea of Kurds gaining autonomy in Syria but increasingly sees them as a counterweight to al-Nusra.
Syrian Kurds have fought al-Nusra in recent weeks, winning control of territory including Ras al-Ain, a town on the Turkish border. Turkish officials have quietly met Syrian Kurdish leaders.
The Barzani adviser said Iraq's Kurdish region was already assisting its kin by hosting and funding meetings and conferences of Syrian Kurdish leaders and using its influence abroad to win support for their cause.
It was not immediately clear what had precipitated the sudden refugee influx of recent days. The border was apparently opened on Thursday after being largely shut since May.
After days in which refugees clambered across the rickety pontoon bridge, it was closed to them and opened only to commercial traffic, UNHCR said on Monday, adding that refugees had switched to another route.
Some refugees who spoke to Reuters described hunger in the Kurdish-populated areas on the Syrian side of the frontier. Others said they had attempted to cross before but been turned back, finally making their way across now after hearing that the long-shut border was again open.
More than 1.9 million Syrian refugees have registered in neighboring countries as well as Egypt since the uprising against Assad began in March 2011. Prior to the latest exodus, they included 154,000 registered in Iraq.
Most Syrian refugees are ethnic Arabs fleeing a largely sectarian conflict between mainly Sunni Muslim rebels and Assad, a member of the Alawite minority offshoot of Shi'ite Islam.
Syrian and Iraqi Kurds are mostly Sunnis, but have tended to fight for their ethnic interests in both states, rather than as members of one of the sectarian factions among majority Arabs.
(Additional reporting by Stephanie Nebehay in Geneva; Writing by Peter Graff; Editing by Alastair Macdonald)