At least 50 rebels were killed and 17 Sri Lankan sailors missing after a sea battle Thursday instigated by the Tamil Tigers left the country on the brink of civil war. Tamil Tigers sank a navy patrol boat off the northern coast as it escorted a troop transport carrying 710 soldiers. In retaliation, the navy downed five rebel vessels and the air force launched airstrikes on guerrilla-held territory. The escalation in violence could mark a return to civil war, as a 2002 cease-fire that stopped almost two decades of fighting appears increasingly unlikely to last. Full Story