BY BEN HUBBARD

Associated Press

BEIRUT

--Airstrikes by Syrian jets and shells from tanks leveled a neighborhood in a restive city near the capital of Damascus on Tuesday, killing 18 people, and at least five rebel fighters died nearby in clashes with regime troops, activists said.

The airstrikes on the city of Douma, northeast of the capital, left residents scampering over a huge expanse of rubble and using their hands to dig up mangled bodies, according to activist videos posted online.

Scenes of vast destruction like those from Douma on Tuesday have grown more common as rebels seeking to topple President Bashar Assad have made gains on the ground, and Assad's forces have responded with overwhelming air power.

In the past weeks, anti-regime activists say about 150 people have been killed a 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.

The death toll for what was supposed to be a four-day cease-fire ending Monday exceeded 500.

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, where rebels have control of swathes of territory.

The international community remains at a loss about how to stop the Syria 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.