Stunned survivors of North Korea's artillery strike against a remote island recounted the shelling Wednesday to a nation furious and on edge over one of the worst attacks since the Korean War.

The discovery of two dead civilians among the blackened rubble on Yeonpyeong island raised the toll to four and heightened the rage, as street protesters burnt the North Korean flag and newspapers called for revenge.

In a sign of the unusually raw nerves in a nation accustomed to high tensions with its nuclear-armed neighbour, supermarkets near the conflict area reported a rush on emergency supplies such as bottled water and noodles.

Residents who fled Yeonpyeong arrived at Incheon port west of Seoul Wednesday, recounting how the calm of their remote island was shattered by a barrage of shells that crashed into shops and homes the previous day.

Fishing boat skipper Kim Kil-Soo, 51, said he was taking a rest at a fishermen's dormitory when the first explosions blew out the windows.

"We were confused and at a total loss... I heard the shrill noise of incoming shells," he said, recounting how he saw shelves topple over in offices and a supermarket. "I thought at that time we were at war."

Kim and other panicked residents rushed into a basic air-raid shelter which quickly filled with the acrid stench from the explosions and fires.

"It was hard to breathe even inside the shelter because of the thick smoke," Kim said. "The whole village was covered in smoke."

"I was at the bunker when the second round of shelling started," Cho Soon-Ae, a 54-year-old woman, told Yonhap news agency. "The whole place trembled every time a shell was fired. I could feel my body burning with fear."

An exodus from the island continued Wednesday as 346 villagers, including 74 children, arrived at port on two coastguard ships. Two were taken to hospital, one with hearing damage, the other with smoke inhalation.

They left behind only several hundred residents on the island, where the explosions destroyed 22 buildings according to latest figures, knocked out electricity to half the population and started fires that blackened 25 hectares (62 acres) of forest.

Incheon City said restoration work would cost some 40 million dollars.

South Koreans often shrug at the threat of living within range of North Korea's arsenal, which includes missiles and chemical weapons -- but this week's attack drove home the reality of the threat.

Major newspapers angrily branded North Korea's artillery attack, which also killed two marines and injured 18 people, as a war crime and many said that their country must not hesitate to strike back.

"A club is the only medicine for a mad dog," said the Dong-A Ilbo daily, while the Chosun Ilbo newspaper warned: "North Korea is putting a dagger to our throat. Let's retaliate against North Korea's illegal attacks immediately, sternly and precisely."

Others voiced similar views in street protests and online chat forums.

Even for those just going about their daily lives, the military escalation threw into sharp focus the threat their nation must grapple with.

"I don't know what we should do," said university student Park Wan-Jin, 20.

"I don't know whether to isolate North Korea with economic sanctions and hold them to blame for their provocative actions -- or to go for an eye for an eye, a tooth for a tooth."

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