
North Korea has launched three short-range ballistic missiles into the Sea of Japan Saturday in a further taunting of US president Donald Trump - but they were all duds.

The US military said that two of the missiles failed in flight and the other blew up 'almost immediately'. They were launched between 6.19am and 6.49am local time in North Korea and landed to the east of North Korea’s Kangwon province.

South Korea's Office of the Joint Chiefs of Staff said it was analysing the missiles.

It said: 'The military is keeping a tight surveillance over the North to cope with further provocations'.

It comes as a US-South Korea joint military exercise is under way and as category 4 Hurricane Harvey moves towards Texas.

North Korean soldiers participating in a target-striking contest of the special operation forces of the Korean People's Army (KPA) to occupy islands at an undisclosed location in North Korea

This image made from video aired by North Korea's KRT on Saturday, showing Kim Jong Un inspecting soldiers during what Korean Central News Agency called a 'target-striking contest'

Pyongyang later said it had a plan to fire missiles at the US territory of Guam, while President Donald Trump said any threats would be met with 'fire and fury'

South Koreans - living under constant threat of attack from their belligerent northern neighbours - had to wake up to the launch at 6.49am local time.

Two of the missiles landed off the east coast of South Korea's Kangwon province after flying 155 miles in a northeasterly direction.

A spokesman for US Pacific Command said none of the missiles, which it said were launched near Kittaeryong, had posed a threat to either North America or the US Pacific territory of Guam.

'The first and third missiles... failed in flight. The second missile launch... appears to have blown up almost immediately,' said the spokesman, Commander Dave Benham, adding that the launches happened over a span of 30 minutes.

The news was immediately reported to President Moon Jae-in.

North Korea has previously conducted dozens of missile test. Pictured: The launch of a surface-to-surface medium long-range ballistic missile Pukguksong-2 at an undisclosed location

Kim Jong Un, second right, speaks with officials during what Korean Central News Agency called a 'target-striking contest' at unknown location in North Korea

North Korean soldiers look at South Korea across the Korean Demilitarized Zone (DMZ) on August 26

Japan's NHK broadcast said the projectiles did not appear to be objects that could threaten Japan's safety.

Yoshihide Suga, the Japanese government's top spokesman, told reporters in Tokyo Saturday morning: 'We confirmed that no ballistic missiles have fallen onto our country's territory or EEZ (exclusive economic zone).'

'We confirmed there was no direct impact on our country's security. Our prime minister told us to remain on high alert and do our best to respond to any situations in order to protect our people's lives and property.'

The launch is the first by the North since it test-fired a missile on July 28 that could have been designed to reach 6,200 miles, putting parts of the US mainland within reach.

The North tends to test-fire balistic missiles or other projectiles - including those from long-range multiple rocket launchers - in response to US-South Korea joint military exercises.

Pictured: The general area where the surviving missiles are reported to have landed

A man watches a TV screen showing file footage of North Korea's missiles launch at the Seoul Train Station in Seoul

A North Korea Scud-B missile (C) is displayed at the Korea War Memorial Museum on Saturday in South Korea

Tens of thousands of South Korean and US troops are taking part in the 'Ulchi Freedom Guardian' joint military drills, a largely computer-simulated exercise that runs for two weeks in the South.

The Stalinist autocracy of North Korea has conducted two nuclear tests and dozens of missile tests since the beginning of last year, defying world powers and raising fears of a devastating conflict breaking out in East Asia.

On Wednesday, Kim ordered the production of more rocket engines and missile warheads during a visit to a chemical institute of the Academy of Defence Science, an agency that he fostered to develop its ballistic missile programme.

Diagrams and what appeared to be missile parts shown in photographs published in the North's state media suggested Pyongyang was pressing ahead with building a longer-range ballistic missile that could potentially reach any part of the US mainland.

It is also believed to be developing a solid-fuel missile that could be used for submarine launches.

North Korea's state media earlier on Saturday said that leader Kim Jong Un inspected a special forces training session that simulated attacks on South Korean islands along the countries' western sea border in what appeared to be a response to the ongoing US-South Korea war games.

Kim reportedly told his troops that they 'should think of mercilessly wiping out the enemy with arms only and occupying Seoul at one go and the southern half of Korea.'

A North Korea Scud-B missile (C) is displayed at the Korea War Memorial Museum in Seoul, South Korea, after ballistic missiles were launched into the East Sea

North Korean army soldier looks at the South side at the border village of Panmunjom in Paju. Tensions are high after missile tests

The Korean Central News Agency said that the 'target striking contest' involved war planes, multiple-rocket launchers and self-propelled guns that attacked targets meant to represent South Korea's Baengnyeong and Yeonpyeong islands before special operation combatants 'landed by surprise' on rubber boats.

The border islands have occasionally seen military skirmishes between the rivals, including a North Korean artillery barrage on Yeonpyeong in 2010 that left two South Korean marines and two civilians dead.

Pyongyang previously said it had a plan to fire missiles at the US territory of Guam, while President Donald Trump said any threats would be met with 'fire and fury'.

Earlier this week, North Korean state media showed Kim standing next to the diagram of an intercontinental ballistic missile more powerful than any it has previously tested.

The image of the three-stage rocket known as the Hwasong-13 suggested he is fiercely pursuing the creation of a weapon capable of striking anywhere on the US mainland

It followed an escalation in the war of words between the country and US President Donald Trump.

North Korea condemned the military drills the US is conducting with the South and branded Trump 'weird' and 'ego-driven', not long after Trump claimed Kim was starting to 'respect' him.

Kim also threatened to turn the US into 'a heap of ashes' in response to the Ulchi Freedom Guardian drills currently being held in South Korea.

Earlier today, the UN said North Korea had increased its efforts to produce parts for a new nuclear reactor.

Kim Jong-un's Stalinist autocracy has threatened to fire missiles near the US territory of Guam. Above, Kim Jong Un guides a target-striking contest of the special operation forces of the Korean People's Army (KPA) to occupy islands in a picture released on Friday

North Korea has increased its efforts to produce parts for a new nuclear reactor, the UN nuclear watchdog warned yesterday

North Korean state media recently showed Kim Jong-un (pictured) standing next to the diagram of an intercontinental ballistic missile

Trump tweeted about the hurricane on Friday afternoon saying the government was ready to respond

The latest taunts from Kim come while Trump deals with matters closer to home as he prepared for Hurricane Harvey to hit Texas.

Trump departed the White House for Camp David on Friday afternoon, he responded when asked what message he had for the people of Texas: 'Good luck to everybody. They're gonna be safe. Good luck to everybody. Good luck.'

Trump tweeted in the afternoon on Friday that he had arrived at Camp David and was continuing to monitor the hurricane.

Eight million Texans are under hurricane warnings, with an additional one million under tropical storm warnings, as landfall quickly approaches for what could be the most powerful hurricane to hit the US in 12 years.

The National Hurricane Center's official five-day forecast Friday has Harvey slamming the central Texas coast, stalling and letting loose with lots of rain.