South Korea's navy is to build an advance base on a frontline island to bolster defences near the disputed Yellow Sea border with North Korea, officials said Tuesday.

The navy has been given local government approval to reclaim 23,489 square metres (250,000 square feet) at Baengnyeong island to build the base, said an official at Incheon city, west of Seoul, which oversees the islands.

The defence ministry said the navy would build a dock for small warships but declined to give details.

Yonhap news agency said the new base would include barracks and a training ground and accommodate about 100 troops. It would be completed by the end of 2014 at a cost of 42.5 billion won ($36.6 million).

Baengnyeong is one of five South Korean islands near the boundary drawn by United Nations forces after the 1950-53 war. Pyongyang refuses to accept the line and insists it should be moved southwards.

The border was the scene of deadly naval clashes in 1999, 2002 and 2009. In November 2010 the North shelled one of the five islands, Yeonpyeong, and killed four South Koreans including two civilians.

The South has since strengthened manpower and weaponry on the islands to forestall any fresh attack. North Korea has reportedly completed a base for troop-carrying hovercraft at Koampo, 50 kilometres (31 miles) north of Baengnyeong.

Japan official in N. Korean 'leak' dead: reports
Tokyo (AFP) June 26, 2012 - A Japanese official being probed as the possible source of news reports claiming China had breached UN weapons embargoes on North Korea has been found dead, reports said Tuesday.

The official, 47, who worked at the foreign ministry's unit in charge of collecting information on terrorism and weapons of mass destruction, was found hanged at his home east of Tokyo last Wednesday, Japanese dailies the Yomiuri, Mainichi and other media reported.

A police spokesman told AFP the death was not thought to be suspicious, but refused to comment further.

Press reports said the official was a target in the ministry's internal probe about the possible leak of highly sensitive information.

Earlier this month detailed reports based on Japanese intelligence appeared in local media about the export from China to North Korea of large vehicles capable of carrying and launching ballistic missiles.

The vehicles were likely those on display at the huge military display in April marking the centenary of the birth of North Korea's founder Kim Il-Sung, said the Asahi Shimbun, which broke the story.

The sale of weapons systems to Pyongyang is banned under UN Security Council resolutions aimed at containing the hermit state's nuclear ambitions.

The Asahi reported at the time that -- at Washington's urging -- Tokyo and Seoul had avoided confronting Beijing in a bid to keep North Korea's patron onside in the international effort to tamp down tensions on the peninsula.

Beijing has denied that it breached UN resolutions.

A senior official at Japan's foreign ministry said it was not known whether there was any link between the official's death and the leak of information to the media, Kyodo News reported.

Asked about the death at a news conference Monday, Senior Vice Foreign Minister Ryuji Yamane said the ministry could not comment on reports of the man's death, but added there had been no plans to penalise him, Kyodo said.