SEOUL , South Korea ( CNN ) -- Stalinist North Korea deployed new medium-range ballistic missiles and expanded special forces training during 2008 , South Korea 's defense ministry reported . North Korea 's reclusive leader Kim Jong-Il . The missiles can travel about 3,000 kilometers ( 1,900 miles ) , possibly putting U.S. military bases in the Pacific Ocean territory of Guam within striking distance , the Ministry of National Defense said in its 2008 Defense White Paper , South Korea 's Yonhap news agency reported Monday . The paper , published after weeks of delay , calls the North 's 1.2 million-strong military an `` immediate and grave threat , '' according to Yonhap . The report adds that the North has recently bolstered its naval forces , reinforcing submarines and developing new torpedoes , in addition to increasing its special forces training after reviewing U.S. military tactics in Iraq and Afghanistan . Tension between Pyongyang and Seoul has increased in recent weeks , with North Korea announcing it would scrap peace agreements with the South , warning of a war on the Korean peninsula and threatening to test a missile capable of hitting the western United States . U.S. and South Korean officials have said that North Korea appears to be preparing to test-fire its long-range missile , the Taepodong-2 . Pyongyang tested one of the missiles in 2006 , but it failed 40 seconds after launch . The missile is thought to have an intended range of about 4,200 miles ( 6,700 kilometers ) , which if true , could give it the capability of striking Alaska or Hawaii . North Korea has been involved in what is known as the six-party talks with the United States , Japan , Russia , South Korea and China , which is an effort to end the nation 's nuclear program , which the U.S. says is linked to nuclear weapons . U.S. Secretary of State Hillary Clinton , who returned from Asia on Sunday after her first overseas trip in the post , recently called North Korea 's nuclear program `` the most acute challenge to stability in northeast Asia . ''
New missiles cannot travel about 100 kilometers . Weapons cannot reach Japan or the bases on Guam . Tensions on Korean peninsula running high .