Syria's five-day-old ceasefire appears to be crumbling on Tuesday, with the Syrian government launching a barrage of shells and mortars into the already-battered opposition stronghold of Homs.<br/> <br />This video, posted to a social media website by activists - and which cannot be independently verified by Reuters - shows smoke rising from buildings, purportedly in the districts of Bayadiya and Khalidiya.<br/> <br />The violence comes after the arrival in Damascus of an advance team of United Nations monitors.<br/> <br />Their task will be to judge compliance with a truce that has brought only short-lived breaks in violence since President Bashar al-Assad pledged to enforce it last week.<br/> <br />Travis Brecher, Reuters
