Young supporters of Kim Jong Il are preparing to "wipe out" the US and Korea with five million nuclear bombs, the head of the republic's youth league has said.
The chilling message from the Central Committee of the Kimilsungist-Kimjongilist Youth League warns that "the Earth will break" if it launches an attack, according to Daily Mail.
It promised to destroy the US and its South Korean neighbours if either shows "a slight provocation," as international tension reaches breaking point.
The warning came as South Korea announced on a high-altitude rocket system to be built on its own soil, giving allies the US powerful weaponry on the peninsula.
North Korea's state-run Korean Central News Agency reported a spokesman saying the youths were "keeping themselves fully combat ready to mercilessly wipe out with five million nuclear bombs the group of devils who are trying to bring a nuclear disaster to the inviolable country."
The warning comes as North Korea fired rockets and torpedoes at mock enemy warships during its 'largest ever' live-fire artillery drills on Tuesday.
Kim Jong-Un's army readied for war as they fired rockets and torpedoes at mock enemy warships during North Korea's "largest ever" live-fire artillery drills on Tuesday.
Hundreds of tanks were lined up along the eastern coastal town of Wonsan in a show of military strength to celebrate 85 years since the North Korean army was created.
Kim saluted the military as he watched the exercises on Tuesday, which involved the firing of more than 300 large-calibre artillery pieces and included submarine torpedo-attacks.
Today, South Korea conducted joint military live-fire drills with the US at Seungjin fire training field in Pocheon, South Korea, near the border with the North.
And in a defiant bit of timing, South Korea have announced that key parts of a contentious US missile defense system have been installed.
The South's trumpeting of progress in setting up the Terminal High-Altitude Area Defense system, or THAAD, comes as high-powered US military assets converge on the Korean Peninsula and as a combative North Korea signals possible nuclear and missile testing.
On the same day, a US guided-missile submarine docked in South Korea.
And the USS Carl Vinson aircraft carrier is also headed toward the peninsula for a joint exercise with South Korea.
The exercise took place as a US guided-missile submarine arrived in South Korea and envoys from the US, Japan and South Korea met in Tokyo to discuss the growing threat posed by North Korea's nuclear weapons and missiles program.
Speculation had mounted that the North could carry out a sixth nuclear test or another missile launch to mark 85 years since the founding of its army.
The South's Yonhap news agency cited a government source as saying the exercise was the North's "largest ever".
Meanwhile, a senior analyst warned that the back-and-forth threats between the US and North Korea could cause a needless stumble into war.
On Monday, President Donald Trump said dictator Jong-Un isn't as strong as he claims to be, and he blamed the international community for not doing more to rein him in.
The "status quo" on North Korea is "unacceptable," Trump told members of the United Nations Security Council at the White House.
"The council must be prepared to impose additional and stronger sanctions," Trump said.
Senior analyst, Jonathan Pollack, at the Brookings Institution says the back-and-forth threats between the US and North Korea "raises the stakes", according to CBS.
"We could stumble needlessly into what would be the biggest crisis in East Asia since the United States intervened in the Korean War in 1950," Pollack warned.
"The situation prevailing on the Korean Peninsula is so tense that a nuclear war may break out due to the frantic war drills of the US imperialists and their vassal forces for aggression," Gen Pak Yong Sik told a meeting of thousands of senior military and civilian officials.
South Korea's Joint Chiefs of Staff said it was closely watching North Korean military action in the Wonsan city area, where it said the drills were being held.
The exercise involved 300 to 400 artillery pieces, but an official from Seoul's Defense Ministry couldn't confirm the details.
Flower-laying and bowing at statues and portraits of the leaders is a regular routine on major anniversaries.
People also gathered in open spaces to take part in organized dancing, another common way to mark holidays.
"Our great leaders founded and wisely led our revolutionary army, and just like that, now our respected Marshal Kim Jong-Un is leading wisely, so even though the situation is tense, we are celebrating the day," said Choe Un Byol, who came with his family to the bronze statues of the former leaders.
North Korea often also marks significant dates by displaying its military capability. It launched a missile one day after the 105th birthday of late founder Kim Il Sung on April 15.
Recent US commercial satellite images indicate increased activity around North Korea's nuclear test site, and third-generation dictator Jong-Un has said the country's preparation for an intercontinental ballistic missile (ICBM) launch is in its "final stage".
The USS Michigan, a nuclear-powered submarine, arrived at the South Korean port of Busan in what was described as a routine visit to rest the crew and load supplies.
Cmdr Jang Wook from South Korean navy public affairs said there was no plan for a drill.
The submarine's arrival comes as the USS Carl Vinson aircraft carrier headed toward the Korean Peninsula for a joint exercise with South Korea.
The US 7th Fleet said two American destroyers were conducting simultaneous maritime exercises with naval ships from South Korea and Japan.
Despite the buildup, Trump has reportedly settled on a strategy that emphasizes increased pressure on North Korea with the help of China, the North's only major ally, instead of military options or trying to overthrow North Korea's government.
Trump told the UN Security Council that they must be prepared to impose additional and stronger sanctions on North Korea.
"This is a real threat to the world, whether we want to talk about it or not," Trump said Monday.
"North Korea is a big world problem, and it's a problem we have to finally solve. People have put blindfolds on for decades, and now it's time to solve the problem."
Nikki Haley, Trump's UN ambassador, said the US is not looking for a fight with Kim and would not attack North Korea "unless he gives us reason to do something". She praised China's increased pressure on North Korea.
When asked about the threshold for US action, Haley told NBC that "if you see him attack a military base, if you see some sort of intercontinental ballistic missile, then obviously we're going to do that".
But asked what if North Korea tests an intercontinental missile or nuclear device, she said: "I think then the president steps in and decides what's going to happen."
The US, Japan and South Korea agreed Tuesday to put maximum pressure on North Korea, the South's envoy for North Korea said after meeting his American and Japanese counterparts in Tokyo.
"We agreed to warn North Korea to stop any additional strategic provocation and take intolerably strong punitive measures against Pyongyang if it goes ahead with such provocations," Kim Hong-kyun told reporters following his meeting with Joseph Yun of the US and Japan's Kenji Kanasugi.
Kim said they discussed ways to get more cooperation from China and Russia, which they agreed is crucial to applying effective pressure on North Korea to abandon its nuclear weapons program. He said they also recognized China's recent steps toward that goal.
Japan's Foreign Ministry announced that China's envoy for North Korea, Wu Dawei, was arriving in Tokyo on Tuesday for talks with Kanasugi that may take place later this week.
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