DAMASCUS, Oct. 9 (Xinhua) -- Islamic State (IS) militants have gained control of one-third of Syria's predominantly Kurdish city of Kobane on the border with Turkey, the London-based Syrian Observatory for Human Rights reported Thursday.

Despite intense clashes overnight between fighters of the Kurdish People's Protection Units (YPG) and the Islamic State militants, the IS group managed to slowly advance from the city's eastern districts into its central part, said the Observatory, adding that the al-Qaida offshoot has also succeeded to capture a Kurdish intelligence headquarter in northeastern Kobane.

Meanwhile, the U.S.-led anti-terror coalition has renewed its air raids on IS positions in Kobane.

The Observatory, citing sources on the ground in Kobane, said the latest round of airstrikes killed "no less than 45" IS militants and forcing them to "pull back from areas in the city."

Kobane, also known as Ayn al-Arab and home to over 400,000 people, has attracted hundreds of Kurdish fighters to stream through Iraqi and Turkish borders to aid their fellow Kurds, who have seen one of the most ferocious and relentless shelling by the IS against the heart of the city.

Since Sept. 16, IS militants have captured more than 300 villages around Kobane, forcing over 160,000 people to flee to neighboring Turkey.

Kurdish activists have repeatedly warned of grave repercussions if the IS takes full control of Kobane, saying the IS would commit mass massacres against the civilians there and enable the extremist group to link its self-declared capital of the northern province of al-Raqqa with Kobane and the Turkish borders.