South Korean soldiers are killed after North Korea fires dozens of artillery shells across its maritime border prompting a return of fire. Lindsey Hilsum asks whether it shows a change in policy.

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Residents were evacuated after North Korea fired shells at the South Korean island of Yeonpyeong, off the west coast of the peninsula near a disputed maritime border.

At least two South Korean soldiers were killed and others - including a number of civilians - were injured in the biggest attack in years as the country was put on its highest non-wartime alert. South Korea's defence ministry said the attack was "clearly in violation of the armistice" with North Korea.

In Washington, President Obama was awoken in the early hours for a briefing. The White House said the attack was "a particularly outrageous act".

Britain also condemned the attacks. In a statement, the Foreign Secretary William Hague urged North Korea to "refrain from such attacks and adhere to the Korean Armistice agreement".

Russia said the attack was "absolutely unacceptable" adding that it was "important the situation does not cross over into a military conflict."

Tonight North Korea's deputy ambassador to the United Nations opposed any debate in the Security Council and called for talks with the South.

Fire confusion

It has emerged that South Korea was conducting a military drill on the island before the exchange of fire. The military said it had earlier conducted a weapons test but had fired west, rather than north.

This is an intentional and planned attack...and it is clearly in violation of the armistice. South Korean defence official

North Korea said it was South Korea who initiated the firing of shells which promoted it to take military action in retaliation.

"Despite our repeated warnings, South Korea fired dozens of shells from 1pm…and we've taken strong military action immediately," the North's state news agency said.

It is unclear whether North Korea suffered damage in the exchange of fire.

A number of the artillery shells landed on a military base on the South Korean island. The island is about 1.8 miles south of the sea border and 75 miles west of the South Korean capital Seoul.

Channel 4 News investigates the North Korea nuclear question.

YTN television quoted a witness as saying 60 to 70 houses were on fire after the shelling and TV footage showed plumes of smoke coming from the island. It said a South Korean fighter jet had been deployed to the west coast after the shelling.

"Houses and mountains are on fire and people are evacuating. You can't see very well because of plumes of smoke," a witness on the island told YTN.

"People are frightened to death and shelling continues as we speak," the witness said.

The exchange, which lasted for about an hour and then stopped abruptly, was the most serious between the two Koreas in years.

North Korea: is the heir apparent influencing policy?
An author, Kim Myong-Chol, who lives in Tokyo but is described as "an unofficial spokesman" for the North Korean government, is talking up the role of Kim Jong-un, son and heir apparent to President Kim Jong-il, writes International Editor Lindsey Hilsum.

"The young general has proved in the eyes of the Workers Party of Korea and the military that he is decisive and ready to risk war at anytime with the US and Japan over the slightest infringement of the sovereignty and independence of North Korea," he writes.

He says that the 27-year-old "has authored papers on nuclear war strategy, missiles and long-range weapons for use in ground warfare and air-defence, winning the acclaim of military leaders."

Now, this could be complete nonsense – bigging up the previously unknown Kim - or it could indicate that the new Kim is influencing policy. Which would be alarming, as shooting incidents between North and South Korea are on the rise, and a report by a US atomic scientist suggests that the North has vastly stepped up its nuclear programme.

Read more on the World News Blog

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North Korea artillery fire hits South Korea island

China urges peace

China - North Korea's only major ally - has expressed worry about the reports of the latest escalation of tensions on the Korean peninsula.

A spokesman for the Chinese Foreign Ministry, Hong Lei, told a news conference both sides of the divided Korean peninsula should "do more to contribute to peace", and said it was imperative to return to talks aimed at ending North Korea's nuclear weapons programme.

"We have heard reports and express our concern. The situation still needs to be confirmed," Hong said.

"China hopes that the relevant parties will do more to contribute to peace and stability in the region," he added.

North Korean leader Kim Jong-il visited China twice this year to strengthen economic and diplomatic ties. Analysts also believe the visits were in part to gain backing for the anointment of his son, Kim Jong-un, to eventually take over the family dynasty.

'Canary in the mine'
"Conflicts here often have very local causes - such as the pressure on the two militaries at the North/South Korean border. They're often for domestic North Korean consumption and boosting military morale," John Hemmings, Research Analyst at the Royal United Services Institute for Defence and Security Studies (RUSI) told Channel 4 News.

"But as it declines economically, North Korea nonetheless also wants to be taken seriously diplomatically and militarily by other powers, particularly the great powers such as Russia and China which surround it.

"The Korean peninsular has historically been an area of conflict for great powers. The Japanese have occupied it several times, at one point calling it a 'dagger in the heart of Japan'. For Japan, controlling Korea has historically been about extending its 'near abroad', whereas for China it has been about controlling states on its borders, though North Korea is a source of frequent irritation for the Chinese. The Russians were also always interested in extending the influence of their Pacific empire but without putting a lot of thought into it.

"Ultimately though, despite foreign interventions, Korea has still managed to maintain its own sense of national identity and independence.

"For many in the Asia Pacific region, the US military alliance with South Korea is the 'canary in the mine', an early warning signal of US determination to stay by its allies in the region. Naturally, as China begins to take its place as a regional power, this signal becomes vitally important."

Korean dynasty

Kim-Jong-il's son made a public debut earlier this year during a show of military strength. State television broadcast the parade live, giving North Koreans their first real look at the young man expected to succeed his father in the future.

China's ties with the secretive state have become a sore point with Washington after revelations that North Korea appears to have made big steps towards enriching uranium.

The stalled six-party talks bring together China, North and South Korea, the United States, Japan and Russia and have sought to end Pyongyang's nuclear weapons development in return for aid.

The top US envoy on North Korea said in Tokyo today the US would consult with Russia in response to fresh concerns about Pyongyang's uranium enrichment programme.

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