Seoul: South Korea carried out live fire naval drills in a show of strength against the North to mark a year since the sinking of one of its warships which Seoul blames on Pyongyang.
Authorities warned of drills in the Yellow Sea and off the southern coast, but well south of the disputed sea border, Yonhap news agency said on Saturday.
It quoted a military source as saying all three of South Korea`s naval fleets would conduct exercises until Sunday, simulating attacks by North Korean submarines, ships and aircraft.
The South accuses the communist North of torpedoing the Cheonan, a 1,200-tonne corvette, on March 26 last year near the disputed Yellow Sea border, killing 46 sailors. Pyongyang angrily denies the charge.
A Seoul-led multinational probe in May concluded that a submarine-launched North Korean torpedo sank the ship.
Investigators said they had "overwhelming" evidence, including a partial torpedo motor and propeller said to have been dredged from the seabed. They said this matched a type that the North had previously offered for export.
Meanwhile, a commemorative service was held at a national cemetery in the central city of Daejeon, where the 46 sailors are buried.
Relatives sobbed as the names of the deceased were read out.
President Lee Myung-Bak, wearing a black suit and a black tie, laid a wreath of flowers, burned incense and bowed before the altar, on which portraits of the victims stood, surrounded by white chrysanthemums.
On Friday, Defence Minister Kim Kwan-Jin accused the North of plotting fresh attacks, ordering his troops to maintain battle readiness.
The South, which has remained technically at war with its nuclear-armed neighbour since the Korean conflict ended in 1953 with an armistice, rather than a formal peace accord, says its drills are defensive.
The two Koreas came close to the brink of war when the North shelled a border island in November last year, killing two soldiers and two civilians, in protest at military drills near the disputed sea border in the Yellow Sea.