SEOUL, Shawwal 15, 1437, July 20, 2016, SPA -- North Korea said on Wednesday it had conducted a ballistic missile test that simulated preemptive strikes against South Korean ports and airfields used by the U.S. military, likely referring to the launches of three missiles on Tuesday, according to Reuters. The North's leader Kim Jong Un supervised the exercise that successfully tested the simulated detonation of nuclear warheads mounted on missiles, its official KCNA news agency reported. North Korea fired three ballistic missiles that flew between 500 km and 600 km (300-360 miles) into the sea off its east coast, South Korea's military said. "The drill was conducted by limiting the firing range under the simulated conditions of making preemptive strikes at ports and airfields in the operational theater in South Korea where the U.S. imperialists nuclear war hardware is to be hurled," KCNA said. "And it once again examined the operational features of the detonating devices of nuclear warheads mounted on the ballistic rockets at the designated altitude over the target area," it said. --SPA 03:15 LOCAL TIME 00:15 GMT www.spa.gov.sa/w