BEIRUT (AFP) - More than 1,000 people, mostly jihadists, have been killed in Kobane since the Islamic State group launched an offensive on the Syrian town nearly two months ago, a monitor said Sunday.

IS jihadists, who proclaimed a "caliphate" in June straddling territory captured in Iraq and Syria, launched their offensive for the town -- also known as Ain al-Arab -- in mid-September.

"At least 1,013 people have been killed in fighting in Ain al-Arab from the beginning of the offensive till last night," said Syrian Observatory for Human Rights director Rami Abdel Rahman.

Militants from the Sunni extremist IS group accounted for 609 of those killed in the Kurdish town on the Turkish border, he said.

Another 363 of those killed were members of the Kurdish People's Protection Units (YPG), 16 were Kurdish volunteers, and one was a Syrian Arab fighter who had joined the ranks of the Kurds.

There were 24 civilians among the dead, said the director of the Britain-based group which relies on a network of sources on the ground for its information.

The toll for jihadists excludes those killed in U.S.-led strikes on the Islamic State group.

Syrian Kurdish forces have been battling to repel IS militants from Kobane since September 16.

The fighters from the town have been joined by Syrian rebels who have fought both President Bashar al-Assad's regime and IS, as well as by Iraqi Kurd peshmerga forces.