Complex sentence: After serving in the Soviet army he worked for nine years in a Stepanakert factory, then in 1990 he joined the unofficial Karabakh Self-Defense Army, of which he became a deputy commander.
Split into simpler sentences: After serving in the Soviet army, he worked for nine years in a Stepanakert factory. In 1990, he joined the Nagorno-Karabakh Defense Army, of which he became a deputy commander.