libya-tripoli- (urgent)-0821-08

CAIRO, Aug 21 (Reuters) - Rebels fighting for control of the Libyan capital Tripoli have killed 31 of Muammar Gaddafi's forces and captured 42, Al Jazeera television said on Sunday, citing its correspondent. Explosions and gunfire rang out in Tripoli through Saturday night as opponents of Gaddafi launched an uprising and rebel forces edged towards the city, declaring a final push to end his four-decade rule. (Reporting by Omar Fahmy; Writing by Dina Zayed)