Moscow, Damascus deny attacking as UN official warns bombing could be war crime

Syria's cease-fire has faltered further after an aid convoy was hit by airstrikes, with a monitoring group saying at least 12 people were killed in the attack, mostly truck drivers and Red Crescent workers.

The strikes late on Monday came just hours after the Syrian military declared the weeklong US-Russian brokered cease-fire had failed. The United States said it was prepared to extend the truce deal and Russia suggested it could still be salvaged.