Isa Huso, a member of the Supreme Kurdish Council diplomacy committee was assassinated as he left his house at 0900 GMT in the Syrian Kurdish city of Qamishli, the Firat news agency reported on its website.

The Supreme Kurdish Council is a platform bringing together Kurdish groups in Syria.

Huso, 60, had worked for Kurdish freedom and actively participated in the founding congress of the Kurdish Democratic Union Party (PYD).

The PYD is the main Kurdish party in Syria and is considered a branch of Turkey's outlawed Kurdistan Workers' Party (PKK).

The Firat report did not say who is suspected of the killing.

Syria's Kurds live in areas rich in resources but have long been marginalised under President Bashar al-Assad's regime, which has been accused by rights watchdogs of cracking down on the minority group.

Since the start of the conflict, the Syrian army has withdrawn from most Kurdish areas in the north of the country and the PYD has taken control of some Syrian towns on the border with Turkey.

Huso, married with 10 children, often became a target of the Syrian regime while fighting for freedom. He was arrested five times, subjected to torture and served a one-year prison sentence, according to Firat.