**South Korean search teams have suspended their efforts to reach possible survivors on a sunken warship, because of poor weather conditions.**The move comes a day after a diver died searching the wreckage of the Cheonan, which is lying near Baengnyeong Island, close to the border with North Korea.
Forty-six sailors have been missing since an explosion split the ship in two late on Friday.
A senior official said the blast could have been cause by a North Korean mine.
A defence ministry spokesman in Seoul told the Yonhap news agency waves at the rescue site were up to 2m (6ft) with winds blowing at 10 knots.
“We are temporarily suspending operations. We cannot expect to get near the ship in this condition,” said Won Tae-jae.
The diver who died, one of dozens trying to gain access to the wreckage, reportedly lost consciousness under water. Yonhap said two of the others were in hospital.
On Tuesday, a navy spokesman said the divers were working in “a very vicious environment” with swift currents and poor visibility.
“Our goal is to get into the ship and find any survivors, but at the moment it is extremely hard to do so,” he said.
Fifty-eight crew members were rescued as the 12,000-tonne Cheonan sank.
Officials say others could have survived in water-tight cabins in its stern, and oxygen has been piped through cracks in the vessel to increase their chances of survival.
But divers who reached the ship on Monday reported hearing no response when they tapped on the hull.
More than a dozen South Korean ships and a US vessel are involved in the rescue effort.
South Korean President Lee Myung-bak visited the scene of the wreck on Tuesday and ordered the military onto alert, saying: “Since the sinking took place at the front line, the military should thoroughly prepare for any move by North Korea.”
Defence Minister Kim Tae-young said the explosion could have been caused by a mine laid by the North during the 1950-53 Korean War or intentionally sent floating towards the South Korean vessel by the communist state.
But an internal malfunction has not been ruled out, and military officials said establishing the cause could have to wait until the ship is salvaged.
Pyongyang has made no official comment on the incident.
It does not accept the maritime border, known as the Northern Limit Line, which was drawn unilaterally by the US-led United Nations Command at the end of the Korean War and has been the scene of deadly clashes between the navies of the two Koreas.This article is from the BBC News website. © British Broadcasting Corporation, The BBC is not responsible for the content of external internet sites.