New flare-ups over a warship sinking has further fueled tension between the South and North on the Korean Peninsula as both sides vowed to take a hard line following the publication of investigation results of the incident. <br/><br/>Pyongyang went furious about investigation results claiming that the South Korean warship Cheonan was torpedoed by a submarine of the north. It declared the current situation as a phase of war as South Korea vowed to take firm measures against Pyongyang over the sinking of the warship. <br/><br/>The Democratic People's Republic of Korea (DPRK) in the north dismissed the investigation results as fabrication and said it will send a verification team to Seoul to check the results.<br/><br/>The United States has told North Korea that it would be punished for sinking a South Korean warship, but kept troop readiness normal in a sign it did not expect an immediate military flare-up. <br/><br/>State Department spokesman Philip Crowley on Thursday said, the torpedo attack, which cost 46 lives and prompted international calls for new sanctions against the nuclear-armed hermit state, was an unprovoked and unwarranted act of aggression. <br/><br/>Meanwhile, Russia has urged all parties concerned to exercise restraint and caution so that tensions on the Korean Peninsula, which increased recently, do not escalate into a conflict.