http://www.bbc.co.uk/news/world-asia-pacific-11818005Artillery fire on Korean border
Houses on the island are said to be on fire after the artillery exchange
South Korea says it has returned fire after North Korea fired around 200 artillery shells onto one of its border islands, reportedly killing one marine.
The South's military was placed on its highest non-wartime alert after the shells landed on Yeonpyeong island.
North Korea has not yet commented on the incident, in which three marines and two civilians were also injured.
Correspondents say this is one of the most serious since the the Korean War ended without a peace treaty in 1953.
There have been occasional cross-border clashes since, but the latest incident comes at a time of rising regional tension.
North Korea's reclusive leader Kim Jong-il is believed to be ill and trying to engineer the succession of his youngest son. And on Saturday, North Korea showed off what it claimed was a new uranium enrichment facility - potentially giving it a second route to a nuclear weapon.
The move prompted the US special representative for North Korea, Stephen Bosworth, to rule out the resumption of six-party talks on resolving the nuclear issue.
South Korean presidential spokesman Kim Hee-jung also said it was investigating a possible link between the artillery attack and recent maritime exercises near the western sea border earlier on Tuesday.
'Illegal firing'
South Korean officials said artillery rounds landed on Yeonpyeong island, near the disputed inter-Korean maritime border to the west of the Korean Peninsula.
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"A North Korean artillery unit staged an illegal firing provocation at 1434 PM (0534 GMT) and South Korean troops fired back immediately in self-defence," a defence ministry spokesman told AFP.
A resident on the island told the agency that dozens of houses were damaged, while television pictures reportedly showed plumes of smoke rising above the island.
"Houses and mountains are on fire and people are evacuating. You can't see very well because of plumes of smoke," a witness on the island told YTN television station.
"People are frightened to death," the witness added.
South Korea had deployed fighter jets to the island, Yonhap news agency said.
This western maritime border, also known as the Northern Limit Line, has been the scene of numerous clashes between the two Koreas in the past.
In March, a South Korean warship went down near the border with the loss of 46 lives.
International investigators say a North Korean torpedo sank the ship, although Pyongyang has denied any role in the incident.
Since then relations between the two neighbours have remained tense.
