Syria has arrested the leader of the opposition, Riad al-Turk, nearly three years after he was released from prison where he spent 17 years according to a Syrian human rights group.
The Committee for the Defence of Human Rights in Syria (CDHR) said in a statement that Turk, 71, was arrested on Saturday at the clinic of a doctor in the coastal city of Tartous, 300 kms northwest of Damascus, where he was undergoing treatment for a heart ailment.
It was not immediately possible to confirm the report.
CDHR did not say why he was arrested, but Turk had previously called for human rights reform in Syria, a respect of the constitution and the lifting of martial law which has been in effect since 1963.
Turk, head of one of three factions of the Syrian Communist Party, spent 17 years in prison and was released in 1998. His political faction remains banned in Syria.
The CDHR said the arrest was a serious setback for the positive political reform which is being adopted by President Bashar al-Assad .
Assad, 35, took office in July last year after the death of his father late president Hafez al-Assad who had ruled Syria with an iron grip for 30 years.
The new president adopted several political reforms and released 600 political prisoners who belonged to various banned political parties, but diplomats say that an old guard whom he inherited from his late father was opposing his reform plans.