* Bomb planted in politician's car outside his home in Syria
* Attack comes after clashes near Syrian-Turkish border
* No one has claimed the bombing (Adds comment from Kurdish activist, details)
DIYARBAKIR, Turkey, July 30 (Reuters) - A prominent Syrian Kurdish politician was assassinated early on Tuesday outside his home near the Turkish border when a bomb planted in his car exploded.
Isa Huso, a member of the foreign relations committee in the Higher Kurdish Council, a group formed to unite Syrian Kurdish parties, was leaving his house in the Syrian town of Al Qamishli when the bomb exploded, Kurdish political sources said.
Kurdish activist Massoud Akko said Huso, who was in his fifties, was a moderate who was imprisoned several times under Syrian President Bashar al-Assad and during the rule of Assad's late father for campaigning for human rights.
"Huso sought to promote Kurdish rights within a united Syria free from the grip of the Assad regime," Akko, who lives in exile in Norway but was previously a neighbour of Huso in Al Qamishli, told Reuters.
"No one knows who killed him but the fingers point to the militant Islamists. They are the only ones who are targeting Kurds as Kurds," he said.
Turkey's pro-Kurdish Peace and Democracy Party condemned the killing but gave no further details.
The revolt against Assad has evolved from its origins as a peaceful protest movement in March 2011 into a civil war that has killed over 100,000 people.
Syria's ethnic Kurdish minority has been battling both Assad's forces and the Islamist-dominated rebels for control of parts of the north, near the border with Turkey, for several months.
Kurds argue they support the revolt but rebels accuse them of making deals with the government in order to ensure their security and autonomy during the conflict.
The Turkey-Syria border has seen a surge of violence since last week when the strongest local Kurdish group, the Democratic Union Party (PYD) seized control of the border town of Ras al-Ain following days of clashes with the Islamist rebel militants from the al Qaeda-linked Nusra Front.
Reports of Nusra taking back control of the town over the weekend could not immediately be confirmed.
PYD has said it aims to set up an independent council to run Kurdish regions until Syria's civil war ends. Such a move would alarm the Syrian rebels and neighbouring Turkey, both wary of a possible Kurdish state.
(Additional reporting by Khaled Oweis in Amman, Writing by Humeyra Pamuk; Editing by Nick Tattersall and Raissa Kasolowsky)