Japan's defence chief has ordered the armed forces to shoot down any North Korean ballistic missiles that threaten to hit the country, according to media reports. Defence Minister Itsunori Onodera issued the order on Thursday -- without publicly announcing it -- after North Korea launched two medium-range ballistic missiles on March 26 towards the Sea of Japan (East Sea), Kyodo News and other media said on Saturday, quoting a government source. A mid-range missile fired from North Korea would be capable of reaching Japan. Under the order, the country's so-called Self-Defence Forces will destroy North Korean ballistic missiles "if any are launched and threaten to fall within Japanese territory", Kyodo said. Defence ministry officials could not confirm the reports Sunday. Japan has issued similar orders in the past before the North launched long-range missiles. In response to the order, an Aegis-equipped destroyer carrying interceptor missiles has been deployed to the Sea of Japan (East Sea), Kyodo's source was quoted as saying. The Aegis has sophisticated computer and radar technology to guide weapons to destroy enemy missiles in flight. On Sunday US Defence Secretary Chuck Hagel said in Tokyo that his country planned to send two more Aegis-equipped destroyers to counter the threat posed by North Korea's "provocative" actions including recent missile launches. The two ships would join five US Aegis vessels already stationed in Japan. The latest shoot-down order brings to five the number of similar directives issued since 2009, the reports said, when North Korea fired a missile which it described at the time as part of a satellite launch.