Seoul: South Korea's Marine commander on Saturday vowed "thousand-fold" revenge for a North Korean attack that killed two servicemen as protesters demanded tougher action by the government against its reclusive neighbour.
President Lee Myung-bak told ministers and aides to be ready for further "provocation" by North Korea during joint military manoeuvres with the United States that start on Sunday.
"There is the possibility that North Korea may do some unexpected action, so please perfectly prepare against it through cooperation with the Korea-US joint force," Lee was quoted by a spokesman as saying.
The two Marines were honoured with a gun salute as families wailed and grim-faced officials saluted the funeral cortege, four days after North Korea rained shells on a tiny island in the heaviest attack on South Korea since the 1950-53 civil war.
Two Marines and two civilians were killed in the attack. South Korea responded with artillery fire 13 minutes later, but it was not clear what damage was caused.
"All Marines, including Marines on service and reserve Marines, will avenge the two at any cost, keeping today's anger and hostility in mind," said Lieutenant General Yoo Nak Joon, commander of the South Korean Marine Corps.
"We will put our feelings of rage and animosity in our bones and take our revenge on North Korea."
The funeral was followed by anti-North Korea protests in the capital as a US nuclear-powered aircraft carrier headed for the manoeuvres with South Korea, infuriating North Korea and prompting a warning from its only major ally, China.
"It's time for action. Time for retaliation. Let's hit the presidential palace in Pyongyang," shouted close to 1,000 Marine veterans in downtown Seoul who burnt photographs of North Korean leader Kim Jong-il and his anointed successor, son Kim Jung-un.
Former members of the "Underwater Demolition Team", practised in sabotage, protested against North Korea and against the government for ignoring their sacrifices on spy missions. Scuffles broke out and police used fire-extinguishers to break up the crowd.
"We can not help expressing our anger about the behaviour of the defence ministry and the government in general that failed to take due retaliatory action," the group said.
South Korea's new defence minister called for tougher action, local media reported. A Seoul newspaper also reported the government plans to sharply increase defence spending next year.
Regional giant China has said it is determined to prevent an escalation of the violence but warned against military acts near its coast as US and South Korean forces prepare for exercises in the Yellow Sea.
A North Korean website (http://www.uriminzokkiri) operated by the government propaganda agency said the war drills were "another unforgivable military provocation".
"(The North) will make the stronghold of the enemy a sheet of flames if they violate its territory even by 0.01 mm."
The US military said the exercises, planned long before Tuesday's attack, were designed to deter North Korea and were not aimed at China.
"We've routinely operated in waters off the Korean peninsula for years," said Captain Darryn James, a Pentagon spokesman. "These latest provocations have been by the North and they need to take ownership of those, not us."
US Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, said North Korea's nuclear ambitions and leader Kim Jong-il's unpredictability increased the threat of regional instability.