Rebel fighters killed 16 Syrian soldiers in a battle in the northern Syria town of Daret Azza on Sunday, the opposition Syrian Observatory for Human Rights said.
Sunday's bloodshed, which the opposition group said included 53 civilian deaths and 27 regime soldiers across Syria, came a day after the Syrian regime announced a new government that retained its top security officials.
Government helicopters launched rockets toward civilian homes in Daret Azza, in Syria's Aleppo province, the opposition Local Coordination Committees of Syria said.
Demonstrations calling for the ouster of President Bashar al-Assad and his regime were also seen in two sections of the turbulent city of Deir Ezzor, according to the LCC.
Regime forces shelled the Aredy neighborhood in Deir Ezzor, while intermittent gunfire was heard in most areas, the LCC said. Sniper fire killed two young men near Ghassan Aboud roundabout Sunday, it said.
Intense shelling was witnessed in the city of Homs, where several buildings were destroyed, the LCC said.
Seven Syrian military pilots defected to Jordan over the weekend, the Syrian opposition said, although a spokesman for Jordan's goverment said only one pilot is known to have been granted asylum. Jordan will not hand the defected pilot back to Syria, spokesman Sameh Ma'ayta said.
The Syrian regime announced a new government just weeks after parliamentary elections.
Riad Hijab, who served as minister of agriculture and agrarian reform, is the new prime minister, al-Assad said in a decree. A longtime member of the ruling Baathist party, Hijab also governed the Syrian provinces of Latakia and Quneitra during his political career.
The country's top diplomat, Foreign Minister Walid Moallem, is keeping his post.
Two top security officials, Defense Minister Dawood Rajiha and Interior Minister Mohammad Ibrahim al-Shaar are staying in their jobs as government forces clamp down on an anti-regime uprising.
The Syrian government -- which has asserted its support of reform and change during the 15 months of unrest -- touted a "wide turnout" for its May parliamentary elections, when more than 7,000 candidates vied for 250 parliamentary seats.
Members of the opposition regarded the elections as a sham. They said a vote for any of the candidates amounted to a vote for al-Assad, whose family has ruled the country for 42 years. They argued that the government is only interested in maintaining its power by any means and urged Syrians to boycott the elections.
Since the anti-government uprising started in March last year, more than 15,000 people in Syria, mostly civilians, have been killed, according to the Syrian Observatory for Human Rights. The United Nations has said that at least 10,000 people have been killed in the conflict.
CNN cannot confirm specific reports of violence in Syria because the government has restricted access to the country by international journalists.
Opposition groups say the violence began when a government crackdown on peaceful protesters generated a nationwide uprising, including the armed resistance. Syria consistently blames terrorists for the violence.