YEONPYEONG ISLAND, South Korea – South Korea’s president ordered more troops to a front-line island and dumped his defense minister Thursday as the country grappled with lapses in its response to a deadly North Korean artillery strike.

In scenes reminiscent of the Korean War 60 years ago, dazed residents of Yeonpyeong island foraged through blackened rubble for pieces of their lives and lugged their possessions down deserted streets strewn with bent metal after Tuesday’s hail of artillery. The barrage darkened skies, set off fierce blazes, killed four South Koreans and raised fears of an escalation that could lead to full-scale war.

“It was a sea of fire,” resident Lee In-ku said, recalling the flames that rolled through the streets of this island that is home to military bases as well as a fishing community famous for its catches of crab. The spit of land is just seven miles from North Korea, but had only six pieces of artillery.

Despite warnings from North Korea that any new provocation would be met with more attacks, Washington and Seoul pushed ahead with plans for military drills starting Sunday involving a nuclear-powered U.S. aircraft carrier in waters south of this week’s skirmish.

The exercises will likely anger the North — the regime cited South Korean drills this week as the impetus behind its attack — but the president said the South could little afford to abandon such preparation now.

“We should not ease our sense of crisis in preparation for the possibility of another provocation by North Korea,” spokesman Hong Sang-pyo quoted President Lee Myung-bak as saying. “A provocation like this can recur any time.”

Washington and Seoul also ratcheted up pressure on China, North Korea’s main ally, to restrain Pyongyang.

Chinese Premier Wen Jiabao responded by calling on all sides to show “maximum restraint” and pushed again to restart the six-nation talks aimed at persuading North Korea to dismantle its nuclear programs in exchange for aid.