Damascus: An opposition activist who had called for greater democracy in Syria was released on Wednesday after completing her full 30-month jail sentence, a rights group said.

"The Syrian authorities today released Fidaa Horani who has completed her full prison sentence," the London-based Syrian Observatory for Human Rights (SOHR) said.

It said four opposition activists, including Horani, have been freed since Sunday.

They are among 12 activists who signed the Damascus Declaration calling for democratic change and were sentenced to 30 months in prison in October 2008 for "damaging the state."

"The other leaders of the Damascus Declaration are expected to be released in the coming days," SOHR said.

Syrian secular opposition groups and the London-based Muslim Brotherhood signed a document in 2005 known as the Damascus Declaration demanding "radical democratic change" in Syria.

Several of its members were subsequently arrested.