The South Korean navy on Thursday began manoeuvres on submarine defence off its western coast amid tensions with North Korea over the sinking of a South Korean warship, DPA reported.
The exercises were conducted far from the disputed sea border with North Korea in the Yellow Sea, the Yonhap News Agency reported, citing military officials.
The Cheonan corvette was sunk March 26 near that border. South Korea and an international team of investigators blamed North Korea for sinking the ship with a submarine-fired torpedo, killing 46 sailors.
The one-day drills off Taenan, about 150 kilometres south-west of Seoul, involve 10 warships, including a 3,000-ton destroyer, Yonhap said.
Depth charges and ship-mounted guns were to be tested in the exercises, it said.
Last week's release of the findings of the Cheonan's sinking have caused tensions on the Korean Peninsula to rise substantially. South Korea banned trade with its neighbour, said it would take the sinking to the UN Security Council and announced a resumption of propoganda broadcasts from loudspeakers at the inter-Korean border.
North Korea, which has denied involvement in the sinking, cut off all ties with the South and has toughened its language toward Seoul, threatening that if its neighbour undertakes any retaliation, it would respond with tough measures that could include war.