Warplanes from the U.S.-led coalition carried out airstrikes Saturday near a key Syrian city besieged by Islamic State fighters, providing some relief to defenders who complain they are outgunned by the al-Qaeda-
inspired group.

Kobane is on the border with Turkey, and capturing it would give the militants strategic control of a new stretch of the frontier and possibly a new route between Turkey and Syria.

“We have reports that 35 [Islamic State] fighters were killed in the strikes, and tanks were destroyed,” said Ojlan Esso, a spokesman for the Syrian Kurdish force in Kobane.

He said strikes by the U.S.-led coalition hit three fronts around Kobane.

The U.S. military’s Central Command reported Saturday that a building and two armed vehicles used by Islamic State forces were destroyed at the Kobane border crossing as part of seven airstrikes carried out Friday and Saturday by U.S. and allied military forces across Syria.

Residents in Kobane said the airstrikes were the first to hit Islamic State positions on the front lines around the town. There have been limited strikes near the town in recent days targeting Islamic State supply lines.

Despite the airstrikes, though, Islamic State fighters did not halt their offensive.

The Islamic State “moved a few miles into Kobane, and Kurdish fighters pulled out,” said Kovan Direj, a resident just outside the city. “But we cannot say that ISIS took the town because there is still fighting going on.”

Fighters with the Islamic State, also known by the acronym ISIS, began their march toward Kobane on Sept. 15, and Syrian Kurdish fighters in the area have been trying to stop them.

“We know ISIS is going to do these kind of things, devote resources to areas where they perceive a weakness,” said Salman Shaikh, director of the Brookings Doha Center and a fellow at the Center for Middle East Policy. “Strategically, this is an area they’ve been trying to get hold of for a while.”

For more than a week, Kurdish leaders from Iraq and Syria have been calling for the U.S.-led coalition to strike the Islamic State fighters near Kobane. The Kurds say their weapons are no match for sophisticated arms in the hands of the militants, who looted Iraqi army bases as they took over swaths of Iraq in June.

“ISIS brought support last night from Raqqah,” Direj said, referring to the Syrian city the militants use as their self-declared capital. He said witnesses saw 18 vehicle-mounted Doshka heavy machine guns “and cars full of militants.” The fighters attacked on three fronts, he said.

But bombing near Kobane is politically complicated for the U.S.-led coalition. One of the main groups fighting there is the Syrian Kurdish YPG — or Kurdish People’s Protection Units — which is linked to Turkey’s Kurdistan Workers’ Party, or PKK, designated a terrorist organization by the U.S. government. The PKK has fought the Turkish military for decades for self-rule, in a conflict that has left tens of thousands dead.

Most of the strikes against the Islamic State militants in Syria have been on their weapons storage facilities, supply routes and sources of revenue, such as oil refineries they have seized.

The loss of Kobane would be a blow to the U.S.-led campaign against the Islamic State, a group that President Obama has pledged to destroy.

More than 160,000 refugees — most of them Syrian Kurds — have crossed into Turkey in the past 10 days, and as the heavy fighting continues in the Kobane area, more are expected to join them. The United Nations has said this is one of the heaviest refugee flows in the three years of war in Syria. Turkey is already hosting 1.5 million Syrians who fled the fighting in their country.

Suzan Haidamous in Beirut contributed to this report.