By Hyonhee Shin North Korea claims successful test to develop multiple warhead missileSEOUL, - North Korea has successfully conducted an important test aimed at developing missiles carrying multiple warheads, state media agency KCNA said on Thursday, a claim rejected by South Korea as "deception" to mask a failed launch. North Korea said the test was carried out on Wednesday using the first-stage, solid-fuel engine of an intermediate-range ballistic missile. The dispatch came a day after South Korea's military said North Korea had launched what appeared to be a hypersonic missile off its east coast that exploded in midair. "The purpose was to secure the capability to destroy individual targets using multiple warheads," it said. "Today North Korea disclosed something, but we believe it's simply a means of deception and exaggeration," Lee Sung-joon, the spokesman for South Korea's Joint Chiefs of Staff, told a briefing.