The British-based observatory, whose estimates of death tolls in the Syria conflict are widely quoted by media organisations, says nearly 1,400 people have died in total since 16 September, when the Islamists began to attack.

The town, known as Ein al-Arab in Arabic, occupies a strategic location at a key border crossing between Syria and Turkey.

Islamic State (IS) fighters initially pushed back Kurdish YPG and YPJ forces, forcing them to abandon nearby villages and retreat into the town amid fierce street fighting.

But on 27 September the US-led coalition formed to fight the fundamentalist group began to bomb IS, inflicting heavy losses.

Kurdish forces were able to bolster Kobani's defences when the Turkish government - widely criticised by Kurds for failing to help them fight US - allowed peshmerga units from northern Iraq to reinforce the town.

The Syrian Observatory for Human Rights (SOHR) puts the death toll after 80 days of fighting at 1,381, including 905 IS militants and 431 Kurdish fighters.

SOHR says the IS losses include 23 suicide bombers, while the Kurdish death toll includes a female leader in the YPJ and a number of fighters who were beheaded, including three women.

The group estimates that 27 Kurdish civilians have died, 17 executed by IS, including 2 teenagers. Four civilians were beheaded and four died in an IS bombardment of Kobani.

SOHR says it believes the real death toll for IS could actually be 500 higher than its estimate "because there is absolute secrecy on casualties in the IS, and due to the difficulty of access to many areas and villages that have witnessed violent clashes and bombardment".

Channel4