REUTERS IS UNABLE TO INDEPENDENTLY VERIFY THE CONTENT OF THIS VIDEO OBTAINED FROM A SOCIAL MEDIA WEBSITE<br/> <br />ROUGH CUT (NO REPORTER NARRATION)<br/> <br />Video posted on the Internet on Sunday appears to show masked Syrian fighters working to camouflage a vehicle loaded with explosives.<br/> <br />The vehicle then moves along a track before a second video apparently shows the vehicle exploding in a white cloud of smoke near an army checkpoint at Tamico on the outskirts of Damascus.<br/> <br />Audio on the second video appears to be of heavy fighting following the explosion.<br/> <br />Rebels claim they seized the checkpoint and were now fighting to capture a second one down the road.<br/> <br />The checkpoints, to the southeast of the capital, sit between the rebel-held suburb of Mleiha and the government-held suburb of Jaramana.<br/> <br />Syrian military jets have pounded nearby rebel-held areas. Rebels hold several suburbs ringing the capital but have yet to make deep inroads into the capital, due to a sustain
