Three members of the security forces were killed on Saturday in northern Syria, where fighting raged despite a pledge by President Bashar al-Assad's regime to stop attacking rebels, activists said.
"One officer and two security agents were killed early on Saturday at Hreitan" in Aleppo province, the site of fierce combat for the past several days, the Syrian Observatory for Human Rights said.
The monitoring group said that in the same province, deserters pressed a dawn assault on Ming air base, while others attacked the military intelligence headquarters at Halab al-Jadida St in Aleppo itself, the country's second city.
At Hama in central Syria, the Britain-based observatory reported fighting in several districts of the city between regular troops and deserters, which was confirmed by an activist on the ground, Abu Ghazi al-Hamwi.
"Regular forces launched an assault early on Saturday on the Al-Qussur district, where they burned down the house of an activist," he said.
Hamwi added that tanks bombarded and then "attacked the town of Al-Latamna" in Hama province.
Another activist, Mohammed al-Shami, said that in Damascus province the town of Irbin saw overnight fighting following protests in support of towns being attacked by the military.
The Local Coordination Committees group, which organizes protests at a local level, put on line on Saturday videos of tanks and armored cars deploying in Douma, just 13 kilometers (eight miles) north of the capital.
UN chief Ban Ki-moon on Friday said attacks by government forces violated a UN Security Council demand for an end to hostilities, and urged Assad not to use a 10 April peace plan deadline as an "excuse" for more killing.
At least 35 people were killed on Friday, 22 of them civilians, the Syrian Observatory said, suggesting Damascus's pledge to immediately withdraw forces from protest hubs had gone unfulfilled.
The UN Security Council passed one statement backing envoy Kofi Annan's peace plan and on Thursday agreed on a second "presidential statement" formally endorsing the 10 April limit for Syrian troops and big guns to be pulled out of cities.
Under the statement, the Syrian opposition were to halt military operations no more than 48 hours later.
The United Nations says more than 9,000 people have been killed in the Assad regime's crackdown on the year-old uprising. Activists say more than 10,000 people have died.
