A South Korean navy ship with 104 people on board has sunk off the west coast near North Korea.
The exact cause of the sinking was unclear, but an explosion was reported in the rear of the ship.
South Korean officials have played down earlier suggestions that it may have been the result of a torpedo attack by North Korea.
Fifty eight of those on board were rescued from near Baengnyeong island by several navy and coastguard vessels. It was not clear what had happened to the remaining personnel.
There were reports that another South Korean ship had fired shots toward an unidentified ship in the North following the alleged torpedo attack.
One report, quoting the joint chiefs of staff, said the target turned out to be a flock of birds, the BBC says.