A first group of Iraqi Kurdish peshmerga fighters entered the besieged Syrian town of Kobani on Thursday to help push back the Islamic State of Iraq and the Levant (ISIL) militants who have defied US air strikes and threatened to massacre its Kurdish defenders.

Kobani, on the border with Turkey, has been encircled by ISIL for more than 40 days. Weeks of US-led air strikes have failed to break their stranglehold, and Kurds are hoping the arrival of the peshmerga will turn the tide.

The siege of Kobani – known in Arabic as Ayn al-Arab – has become a test of the US-led coalition’s ability to stop ISIL’s advance, and Washington has welcomed the peshmerga’s deployment.

A first contingent of about 10 peshmerga fighters crossed into Kobani from Turkey, the Britain-based Syrian Observatory for Human Rights said. Kurdish and Turkish officials said a larger deployment was expected within hours.

“That initial group, I was told, is here to carry out the planning for our strategy going forward,” said Meryem Kobane, a commander with the YPG, the main Syrian Kurdish armed group defending the town.