BEIRUT — U.S.-led coalition airstrikes targeted fighters, vehicles and artillery pieces of the Islamic State group on both sides of the Syria-Iraq border Tuesday, including around a beleaguered Kurdish town near the Syrian-Turkish that is under assault by the militants, activists said.

The aerial campaign, which began last week in Syria and last month in Iraq, aims to destroy the extremist faction known as the Islamic State that has seized control of a huge chunk of territory stretching from northern Syria to the western outskirts of the Iraqi capital.

Despite the coalition airstrikes, the militants have pressed their offensive on the town of Kobani, also known by its Arabic name of Ayn Arab, and surrounding villages near Syria's border with Turkey. The fighting has created one of the single largest exoduses in Syria's civil war, now in its fourth year: More than 160,000 fled the area into Turkey the past few days, the U.N. humanitarian chief Valerie Amos said.

"Their fear is so great that many people crossed heavily mined fields to seek refuge," she told the U.N. Security Council.

The Britain-based Syrian Observatory for Human Rights said Tuesday's strikes hit Islamic State fighters east and west of Kobani. The Local Coordination Committees, another activist group, also confirmed the airstrikes on the town's outskirts. Both groups attributed the strikes to the U.S.-led coalition.

The U.S. Central Command said U.S. fighter jets and drones conducted 11 airstrikes Monday and Tuesday in Syria, including three near the Syria-Turkish border that destroyed one artillery piece, damaged another and knocked out two rocket launchers. It said another strike northeast of Aleppo destroyed four buildings occupied by Islamic State militants. Two strikes destroyed vehicles, artillery and a tank in eastern Syria and near the Iraq border.

Kurds and militants battled Tuesday on Kobani's eastern edge, said Ahmad Sheikho, an activist operating along the Syria-Turkey border. He said that members of the local Kurdish militia destroyed two tanks belonging to the Islamic State group. Militants have been hitting the town with mortars and artillery shells. A day earlier, fighting around Kobani killed 57 fighters, including both Kurds and militants, according to the Observartory.

The situation in Kobani was "very difficult," said Nawaf Khalil, a spokesman for Syria's leading Kurdish Democratic Union Party, or PYD.

Just outside Kobani, Islamic State militants captured the deserted Kurdish village of Siftek on Tuesday and appeared to be using it as a headquarters from which to launch attacks on Kobani itself.

The fighting could be seen from a hilltop on the Turkish side of border, in the Karacabey area. From there, spectators — mostly Turkish Kurds — watched the fighting, some using binoculars and cheering on their Syrian Kurdish brethren.

"Long live YPG, long live Apo," shouted one woman, referring to Kurdish rebel leader Abdullah Ocalan, whose group has been fighting Turkey for Kurdish autonomy. Apo is a Kurdish nickname for Abdullah.

In neighboring Iraq, heavy fighting erupted between Kurdish fighters and Islamic State militants in the town of Rabia on the Syrian border, as well as Zumar and Daquq after U.S. airstrikes against the extremists' positions there, said Helmut Hekmut, a spokesman for the Kurdish armed forces known as peshmerga.

Wounded from the fighting were rushed in at least a dozen ambulances down narrow streets to a hospital in the town of Zakho, some 66 kilometers (40 miles) north of the Rabia fighting. Huge crowds of weeping relatives gathered outside the hospital running toward the stretchers bearing the wounded to see if friends or family were among them.

At a makeshift medical clinic in the nearby town of Fishkhabour, officials said some 70 peshmerga fighters were wounded in the heavy clashes. Most of the injuries were from mortar rounds, machine gun fire and snipers, they said.

The U.S. said its aircraft conducted seven strikes in northwest Iraq, destroying seven Islamic State vehicles and damaging one. Four more strikes also hit militant vehicles and fighting positions near the Mosul Dam as well as outside Baghdad.

Meanwhile, Hadi Bahra, the head of the main Western-backed Syrian opposition group, said the U.S.-led coalition's strategy against the Islamic State group should include aerial assistance to moderate rebels, to help them push into areas controlled by the extremists.

"We want two things from the world: Logistical support, training and arming, in addition to aerial coverage of these areas," Bahra, the head of the Syrian National Coalition told the pan-Arab daily Al Hayat newspaper.

Washington and its Arab allies opened the air assault against the extremist group in Syria on Sept. 23, striking military facilities, training camps, heavy weapons and oil installations. The campaign expands upon the airstrikes the United States has been conducting against the militants in Iraq since early August.

Also Tuesday, an international human rights group said Lebanese authorities are failing to protect Syrians, most of them refugees, living in Lebanon from attacks by individuals or groups. Such assaults have intensified since the Aug. 2 cross border attack during which Muslim militants captured 20 Lebanese soldiers and policemen, said the Human Rights Watch. Since then, three soldiers have been killed by their captors.

The attacks against Syrians are taking place in a climate of indifference and discrimination by officials, the New York-based group said, adding the violence appears in some cases to be attempts to expel Syrians from specific neighborhoods or to enforce curfews, it said.


Associated Press writer Burhan Ozbilici in Suruc, Turkey, Vivian Salama in Zakho, Iraq, and Ryan Lucas in Beirut contributed to this report..