(LEAD) S. Korea, U.S. step up surveillance over N. Korea: official

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By Sam Kim
SEOUL, May 28 (Yonhap) -- The armed forces of South Korea and the U.S. raised
their surveillance over North Korea to the second highest level Thursday as the
communist state went ahead with its second nuclear test and threatened war, an
official said.

The last elevation of the five-stage "Watchcon" was in October 2006 when North
Korea conducted its first nuclear test. It was then also ramped up to the second
highest notch.
The decision comes as Pyongyang threatens war on the Korean Peninsula, which
technically remains in a state of conflict after the 1950-53 Korean War ended in
a truce rather than a peace treaty.
On Wednesday, North Korea declared it will no longer abide by the ceasefire,
warning it cannot ensure safe navigation of U.S. and South Korean naval vessels
along the sea border.
"Watchcon II took effect as of 7:15 a.m.," South Korean defense spokesman Won
Tae-jae said in a briefing, adding the five-stage combat alert level, "Defcon,"
remains locked at four.
"Additional intelligence assets, including personnel, will be deployed while
reconnaissance operations over North Korea will increase," Won said. He declined
to give specific details.
The elevation of the surveillance marks the fifth time South Korea and the U.S.
have upgraded Watchon to the second highest level, he said.
The previous elevation lasted two weeks after the North's first nuclear test in
2006, Won said. Watchcon II also took effect in 1999 when the two Koreas clashed
in a naval battle near their Yellow Sea border.
The step-up in surveillance comes as South Korea prepares to host a summit
conference with the leaders of Southeast Asian Nations, or ASEAN, from June 1-2.
South Korea plans to place its 655,000 troops on a heightened alert throughout
the conference in its southern island of Jeju while the U.S. will bolster its
support in intelligence activities.
The U.S. has 28,500 troops stationed in South Korea as a deterrent against North
Korea.
Watchcon II was switched on for the first time in 1982 when North Korea deployed
bombers close to the border. It was also put in effect when North Korea deployed
armed troops on its side of the truce village in the Demilitarized Zone in 1996,
Won said.
samkim@yna.co.kr
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