quote, he could be planning for a last stand. another saying it could be he could put civilians in the crosshairs. but both officials say they just don t know what form a final offensive might take. recent nato airstrikes are clearly upping the ante. our people there are telling us they are under way again tonight. loud explosions being heard in tripoli within the past hour. opposition forces telling us they re making use of the air attacks to try to make progress on the ground. those forces in zawia, fierce artillery fire could be heard today. opposition fighters telling our reporter they could be moving on the capital within a number of days. that could just be optimistic talk on their part. meantime, the opposition says a former libyan prime minister has defected, fleeing tripoli with his family. no sign his former boss momeamm gadhafi is going anywhere and that s the potential problem, a potentially violent and bloody problem. joining us, sara sidner, and commander wesl