Tens of thousands of Syrian Kurds have crossed into Turkey in the past 24 hours, fleeing an advance by Islamic State fighters who have seized dozens of villages close to the border and are advancing on a Syrian town.
Arab media reported the extremists have captured 60 Kurdish villages in the northeastern part of Syria.
Also Saturday, Britain-based Syrian Observatory for Human Rights said more than 300 Kurdish fighters have crossed into Syria from Turkey to defend a Kurdish area from attack by Islamic State militants.
The rights group said the fighters are heading for the border town of Kobani in northern Syria, where Islamic State fighters have been seizing territory for the past week.
Meanwhile, Turkey opened a stretch of the frontier on Friday after Kurdish civilians fled their homes, fearing an imminent attack on the town of Ayn al-Arab. Islamic State fighters are now within 15 kilometers (9 miles) of the town, also known as Kobani, according to a Kurdish commander on the ground.
The Islamic State group's advances in northern Syria have prompted calls for help by the region's Kurds who fear a massacre in Kobani. The town sits in a strategic position on the border and has prevented the radical Sunni Muslim militants from consolidating their gains across northern Syria.
"Clashes started in the morning and we fled by car. We were 30 families in total," said Lokman Isa, 34, a farmer who had crossed into Turkey.
He said Islamic State fighters entered his village, Celebi, with heavy weapons and the Kurdish forces battling them only had light arms.
"They have destroyed every place they have gone to. We saw what they did in Iraq in Sinjar and we fled in fear," he told Reuters in the Turkish town of Suruc.
Turkish Deputy Prime Minister Numan Kurtulmus told CNN Turk television on Saturday that 45,000 Syrian Kurds had crossed a 30-kilometer section of the border since Turkish authorities opened it on Friday.
“The United States, Turkey, Russia, friendly countries must help us. They must bomb Islamic State. All they can do is cut off heads, they have nothing to do with Islam,” said Mustafa Saleh, a 30 year-old water industry worker in Suruc at the site of a boarding school where tents were being set up for refugees.
“I would have fought to my last drop of blood against Islamic State but I had to bring the women and children," Saleh said.
Kurdish lawyer Farhad Bakr said up to 60,000 refugees may have already fled their villages through the Kurdish town of Ain al-Arab and into Turkey.
Bakr called the situation a “humanitarian catastrophe” and urged the international community to intervene.
The Syrian Opposition Coalition issued a statement Saturday, urging the international community to use airstrikes to stop what it called “ethnic cleansing and mass atrocities” in the town of Ain al-Arab.
Al Arabiya TV also reported that Islamic State militants had captured 60 Kurdish villages in northern Syria during the past several days. VOA could not independently confirm the claim.
Kurdish forces have evacuated at least 100 villages on the Syrian side since the Islamic State group's onslaught started on Tuesday and have abandoned control of scores as the militant group gained ground.
"Islamic State sees Kobani like a lump in the body, they think it is in their way," said Rami Abdulrahman, who runs the Syrian Observatory for Human Rights, which monitors Syria's civil war.
IS group executes Kurds
The Islamic State group has executed at least 11 Kurdish civilians, including boys, in the villages it has seized near Kobani, the Observatory said.
More than 300 Kurdish fighters crossed into Syria from Turkey late on Friday to help push back Islamic State group's advance, he said, adding it was not clear which group the fighters belonged to.
“Islamic State is killing any civilian it finds in a village,” Mustefa Ebdi, director of a local radio station called Arta FM, told Reuters by telephone from the northern outskirts of Kobani. He said he could see thousands of people waiting to cross the border into Turkey.
“People prefer to flee than to remain and die,” Ebdi said. “(The Islamic State group wants) to eliminate anything that is Kurdish. This is creating a state of terror
“I confirm that massacres have happened in the villages of eastern Kobani (province),” he added.
On his Facebook page Ebdi said the killing of 34 civilians - women, elderly, children and the disabled - had been documented. He said residents of 200 villages had been forced to flee.
About 1,500 refugees were staying at the camp in Suruc, but most are spread out across the region, staying with relatives.
“It is a very painful situation,” said Fadile Genco, 60, weeping as her eight children gathered around because her 67-year-old husband had stayed on in Syria to fight the militants.
“If my husband does not come what will I do with all the children,” Genco said.
Esmat al-Sheikh, head of Kurdish forces defending the town, said clashes were taking place to the north and east on Saturday.
Islamic State fighters using rockets, artillery, tanks and armored vehicles had advanced further towards Kobani overnight and were now within 15 kilometers, he told Reuters by telephone.
At least 18 Islamic State fighters were killed in clashes with Syrian Kurds overnight as the militant group took control of more villages around the town, according to the Observatory.
Also Saturday, Turkey's prime minister said 49 Turkish hostages seized by Islamic State militants in Iraq in June have been freed.
Ahmet Davutoglu said Saturday the hostages were released earlier in the day and have arrived safely in Turkey.
Islamic State fighters took full control of about 30 villages near Kobani, which had been abandoned by Kurdish forces late on Friday, Abdulrahman said. Another 30 villages were under fire, he said.
Iraqi Kurdish leader Masoud Barzani called on Friday for international intervention to protect Kobani from the Islamic State group's advance, saying the insurgents must be "hit and destroyed wherever they are".
The United States is drawing up plans for military action in Syria against Islamic State fighters who have seized swathes of territory in Syria and Iraq, proclaiming a caliphate in the heart of the Middle East.
Western states have increased contact with the main Syrian Kurdish political party, the PYD, whose armed wing is the YPG, since Islamic State fighters led a lightning advance in Iraq in June.
The YPG said it has 50,000 fighters and should be a natural partner in a coalition the United States is trying to assemble to fight Islamic State militants.
But such cooperation could prove difficult because of Syrian Kurds' ties to the Kurdistan Workers' Party (PKK), a group listed as a terrorist organization by many Western states due to the militant campaign it has waged for Kurdish rights in Turkey.
The PKK on Thursday called on the youth of Turkey's mainly Kurdish southeast to join the fight against Islamic State.
Edward Yeranian contributed to this report from Cairo.