Updated

Air raids by regime forces collapsed expanses of buildings on Tuesday in a rebel-held city that straddles a key supply route from the capital Damascus to Aleppo, Syria's largest city and a main front in the civil war.

While residents dug the bodies of the dead and wounded from the rubble, forces loyal to President Bashar Assad clashed with rebels south of the city targeted by the airstrikes, Maaret al-Numan. Rebels captured the strategic city earlier this month and have been disrupting the flow of military supplies to Assad's forces fighting for control of Aleppo, the country's commercial capital.

Assad's regime has been hammering away at Maaret al-Numan with heavy airstrikes since it was captured on Oct. 10. The battle for the city in many ways reflects the wider civil war. Lightly armed rebels are holding the ground while the regime, with its superior weaponry and numbers, has been unable to dislodge them despite repeated bombardments from the air that kill fighters and civilians alike.

In the past weeks, anti-regime activists say about 150 people have been killed on average every day in fighting. Since the uprising against Assad began in March 2011, they say 35,000 have died.

Tuesday's airstrikes came a day after what activists called the heaviest and most widespread bombing campaign nationwide on what was to be the final day of an internationally sanctioned truce that never took hold. Maaret al-Numan was hard hit Monday's strikes as well.

The death toll for what was supposed to be a four-day cease-fire ending Monday exceeded 500, and activists speculated that the government's heavy reliance on air power reflected its inability to roll back rebel gains, especially in the north of the country near the border with Turkey's where rebels have control of swathes of territory.

The international community remains at a loss about how to stop Syria's violence. The U.S. and other Western and Arab nations have called on Assad to step down, while Russia, China and Iran continue to back him.

Tuesday's airstrikes on Maaret al-Numan, 80 kilometers (50 miles) southwest of Aleppo, left rebel fighters and residents coming through expanses of rubble for bodies, according to activist videos posted online.
  One video showed a man holding up the dead body of a small girl in a red and white shirt and baby blue pants. Other videos showed men carrying bloodied women and children from destroyed buildings.
  The Britain-based Syrian Observatory for Human Rights said the day's airstrikes on the city killed at least seven people, four of them children.

One video showed the bodies of three girls wrapped in white shrouds. Nearby, a man dripped water on the face of a dead older man with a white beard, saying: "Go to heaven dad. May God take revenge."

The Observatory said at least one rebel fighter was also killed in clashes south of the city with regime forces trying to bring in reinforcements from further south.

Activist claims and videos could not be independently verified because of restrictions on reporting in Syria, but the videos appeared genuine and corresponded with other Associated Press reporting on the events depicted.

Violence also flared in and around Damascus, the capital. The Observatory said missiles fired from a fighter jet struck the capital's Jobar neighborhood -- a rare hit in the capital's municipal area. Most of the fighting around Damascus for the past few months has been in suburbs and outskirts, where rebels have managed to challenge the regime.

Syria's state news agency said an "armed terrorist group" had assassinated a high-ranking air force general. Maj. Gen. Abdullah Mahmoud al-Khalidi was gunned down while getting out of his car in the mostly Kurdish neighborhood of Rukn Eddine.

The government views the rebels as terrorists and accuses them of being foot soldiers in a foreign plot to destroy Syria.

Anti-regime activists also reported air raids on several Damascus suburbs, including Arbeen, Zamalka and Douma.

Early Tuesday, Syrian troops clashed with rebels in the Yarmouk camp for Palestinian refugees on the captial's south side. No casualties were reported, and it was unclear if Palestinians fought with either side. Most Palestinian refugees in Syria have tried to remain outside of the conflict, though some have joined the fight.

In Turkey, Foreign Minister Ahmet Davutoglu expressed "great sadness" that the cease-fire called to coincide with a Muslim holiday had failed and said government was done talking to Assad's regime.

"Unfortunately the attacks continued and the Syrian people spent the holidays suffering great pain," Davutoglu told reporters in Ankara. "There would be no meaning to forging a dialogue with a regime that pressed ahead with such a massacre even during the holidays."