The US-led coalition has pounded the Islamic State jihadist group with 31 air strikes in a day, including more than a dozen in the flashpoint Syrian town of Kobane, the Pentagon says.

Friday's 13 strikes in Kobane, which is known as Ain al-Arab in Arabic, destroyed 19 fighting positions, as well as IS buildings, staging areas and a vehicle, the Defence Department said in a statement.

Several tactical units were also hit by fighter and bomber aircraft, as well drones, the statement said.

Fighting over Kobane began in mid-September, when the IS launched a bid to take over the town on the border with Turkey. The US-led coalition has been launching air strikes against the Islamic State group in Syria since September 23.

There were a total of 16 strikes in Syria, where coalition raids also struck a drilling tower, more vehicles, and another staging area.

In Iraq, strikes destroyed an IS rocket system near the town of Al Asad in Anbar province.
The jets and drones also targeted IS vehicles, fighting positions, equipment, tactical units, and a storage container, in a total of 15 raids across seven locations in Iraq.