Syrian opposition activists say government troops have moved into several Damascus suburbs as part of an offensive to drive out rebels who have been trying build a stronghold near President Bashar al-Assad's center of power.

The activists say pro-Assad soldiers backed by dozens of tanks and armored vehicles battled the rebels in the Kfar Batna and Ghouta districts on the eastern outskirts of the capital Sunday. They say four civilians and a rebel were killed in the fighting. The activists said another civilian was killed in the central province of Homs.

In another incident Sunday, Syrian state news agency SANA said what it described as “terrorists” detonated a roadside bomb near a military bus in the Damascus suburb of Sahnaya, killing six soldiers and wounding six others.

Details of the fighting and casualties could not be independently confirmed because Syria bars foreign journalists from operating freely in the country.

Arab League chief Nabil Elaraby said Sunday he is trying to persuade Russia and China to support the regional bloc's plan for ending Syria's months-long unrest. Elaraby was speaking in Cairo before departing on a flight to New York, where he will formally present the initiative to the U.N. Security Council on Tuesday.

The Arab League suspended the operations of its observer mission in Syria Saturday, citing the Syrian government's escalation of a violent crackdown on the 10-month long opposition uprising. Elaraby said the monitors will remain in Damascus until Arab League foreign ministers meet next Sunday to decide whether to pull them out of the country.

Russian Foreign Minister Sergei Lavrov criticized the Arab League's move. In remarks Sunday, he described the observer mission as a useful tool for resolving the Syrian crisis. Moscow is a key military ally of Syrian President Assad and opposes efforts by other Arab states and Western powers to seek U.N. Security Council action against his government.

The United Nations said in December that violence linked to the unrest in Syria has killed more than 5,400 people. But U.N. officials said last week that they have stopped compiling a death toll because it is too hard to obtain information.