North Korean leader Kim Jong Un oversaw a ground test of an upgraded high-thrust solid-fuel rocket engine, state media KCNA reported on Sunday, in the latest move to advance the country's strategic weapons program . The test is a part of a five-year defense plan and involved a carbon-fiber composite engine with a reported maximum thrust of 2,500 kilonewtons, according to KCNA. The news agency did not disclose when or where the test took place. The demonstration "showed the physical and