Rocket fire by jihadists from the Islamic State group hit the besieged Syrian Kurdish town of Ain al-Arab on Saturday for the first time, wounding 12 people, a monitor said.

The report comes as the US-led coalition widened its campaign of air strikes against IS targets to include fighters around the town on the Turkish border, known as Kobane by the Kurds.

"Rockets fired by the IS from hills eight kilometres (five miles) east of Kobane hit the town, wounding 12 people," said Rami Abdel Rahman, director of the Syrian Observatory for Human Rights.

It was the first time IS rockets have hit the town since the assault began on September 16, Abdel Rahman added.

Following the attacks, hundreds of people living on the east side of Ain al-Arab fled for safety into Turkey, he said.

The jihadist advance on the town has already sent 160,000 refugees streaming across the adjacent border.

Saturday was the second time US-led air strikes had been reported around Ain al-Arab since the IS advance began, and the sound of fighting was clearly audible from the Turkish side of the border, an AFP photographer reported.