MYANMAR troops fired at anti-coup protesters yesterday, killing at least 13 people and wounding several, the media said, as a series of small blasts hit the commercial capital Yangon and a Chinese-owned factory was set on fire. The country's military ruler said the civil disobedience movement was "destroying" Myanmar. More than 580 people have been killed, according to an activist group, in the turmoil in Myanmar since a Feb. 1 coup that ended a brief period of civilian-led democracy. Nationwide protests and strikes have persisted since then despite the military's use of lethal force to quell the opposition. Security forces…