UN Secretary-General Ban Ki-moon said Saturday he was "deeply concerned" about the current situation in Syria, and called for an immediate end to the use of violence against peaceful demonstrators in the Middle East country.

"The secretary-general is deeply concerned about the situation in Syria, where more civilian deaths have been reported during the latest popular demonstrations," said a statement issued by Ban's spokesman early Saturday.

Ban "deplores the use of violence against peaceful demonstrators and calls for it to cease immediately," the statement said.

"The secretary-general reiterates his call on the Syrian government to abide by its international human rights obligations."

An armed group on Friday fired from some buildings at civilians and security forces in Syrian city of Douma, near the capital Damascus, killing and wounding dozens, the state-run SANA news agency quoted an official source as saying.

Anti-government protests erupted on Friday morning in various cities including Damascus, Latakia, Banias, Homs and Daraa, where thousands of Syrians took to the streets, calling for freedom and democracy.

Syrian authorities have accused "armed groups backed by foreign powers" of being behind the recent unrest, during which some 50 people were killed, according to official figures.