North Korea on Saturday accused South Korea of using civilians as human shields at an island the North attacked this week, saying the South was publicizing the deaths of two of the civilians as part of a propaganda campaign.

The comments came on the eve of US-South Korean naval maneuvers, and follow a surprise North Korean artillery attack on a small island in the Yellow Sea that houses military installations and tiny fishing communities. The barrage killed two marines and two civilians and sent tensions between the rivals soaring.

North Korea's state news agency says the South should be held responsible because "it took such inhuman action as creating 'a human shield' by deploying civilians around artillery positions."

It said the South "is now working hard to dramatize 'civilian casualties' as part of its propaganda campaign, creating the impression that the defenseless civilians were exposed to 'indiscriminate shelling' all of a sudden from the" North.

South Korea's marine commander vowed severe revenge at a funeral Saturday for two marines killed in the bombardment.

The commander, Maj Gen You Nak-jun, said the retaliation would be a "thousand-fold" as dignitaries and relatives laid white flowers at a funeral altar following Tuesday's attack on a South Korean island that was one of the worst artillery attacks on the country's territory since the 1950-53 Korean War.

As protesters in Seoul demanded their government take sterner action against North Korea, the North issued new warnings against the war games scheduled to start Sunday with a US nuclear-powered aircraft carrier in the Yellow Sea.

The North called the games an "unpardonable provocation" and warning of retaliatory attacks creating a "sea of fire" if its own territory is violated. The comments ran on North Korea's state-run Uriminzokkiri website a day after the North's warnings that the peninsula was on the "brink of war."