( CNN ) -- North Korea says it will attack the Japanese military and `` major targets , '' if Japan shoots down a rocket Pyongyang plans to launch in the coming days , North Korea 's state-run news service , KCNA , reported Thursday . Japan recently deployed its missile defense system in anticipation of North Korea 's planned rocket launch . `` If Japan recklessly 'intercepts ' [ North Korea 's ] satellite for peaceful purposes , the [ Korean People 's Army ] will mercilessly deal deadly blows not only at the already deployed intercepting means but at major targets , '' KCNA reported . Japan recently mobilized its missile defense system in response to the planned North Korean launch , Japanese officials said . The move , noteworthy for a country with a pacifist constitution , is aimed at shooting down any debris from the launch that might fall into Japanese territory . U.S. Navy ships capable of shooting down ballistic missiles have also been moved to the Sea of Japan , a Navy spokesman said . The threat of retaliation comes as North Korea has begun fueling its long-range rocket , according to a senior U.S. military official familiar with the latest U.S. intelligence on the matter . The fueling signals that the country could be in the final stages of what North Korea has said will be the launch of a satellite into space as early as this weekend , the senior U.S. military official said Wednesday . Other U.S. military officials said the top portion of the rocket was put on very recently , but satellite imagery shows a shroud over the stage preventing a direct view of what the stage looks like . The officials said the satellite payload appears to have a `` bulbous '' cover , which could indicate there is a satellite loaded on it . Such a cover protects a satellite from damage in flight . While the sources did not know for sure what the payload is , they did say there is no reason to doubt it is a satellite as indicated by North Korea . Pyongyang has said it will conduct the launch sometime between April 4 and April 8 . It 's a launch that may violate a 2006 United Nations Security Council resolution . Resolution 1718 `` [ d ] emands '' that North Korea `` not conduct any further nuclear test or launch of a ballistic missile . '' `` It raises questions about their compliance with the Security Council Resolution 1718 , '' U.S. Secretary of State Hillary Clinton said last week . `` And if they persist and go forward , we will take it up in appropriate channels . '' Pentagon officials worry less about the payload and more about the launch itself , saying any kind of launch will give the North Koreans valuable information about improving their ballistic missile program . `` I do n't know anyone at a senior level in the American government who does not believe this technology is intended as a mask for the development of an intercontinental ballistic missile , '' U.S. Defense Secretary Robert Gates said on Sunday . Defense analysts say the same rocket could be used to push a satellite into space or deliver a nuclear warhead . Gates noted that while the United States believes it is North Korea 's `` long-term intent '' to add a nuclear warhead to any such rocket , he `` personally would be skeptical that they have the ability right now to do that . '' Gates said that the U.S. military could shoot down `` an aberrant missile , one that was headed for Hawaii ... or something like that , we might consider it , but I do n't think we have any plans to ( do ) anything like that at this point . '' He does not believe North Korea currently has the technology to reach Alaska or Pacific coast . CNN Senior Pentagon Producer Mike Mount contributed to this story .
North Korea says it will attack Japanese military , ` ` major targets , '' if it shoots down rocket . Japan recently mobilized its air defense system in response to planned launch . N. Korea says it would likely launch between April 4 and April 8 . Sources say ` ` bulbous '' shape atop rocket could indicate satellite aboard .