UPDATE:Is It Korean Was Redux? (Was it provoked?)

SEOUL (AFP) – North Korea fired dozens of artillery shells onto a South Korean island on Tuesday, killing one person, setting homes ablaze and triggering an exchange of fire as the South's military went on top alert.

In what appeared to be one of the most serious border incidents since the 1950-53 war, South Korean troops fired back with cannon, the government convened in an underground war room and "multiple" air force jets scrambled.

The firing came after North Korea's disclosure of an apparently operational uranium enrichment programme -- a second potential way of building a nuclear bomb -- which is causing serious alarm for the United States and its allies.

Some 50 shells landed on the South Korean border island of Yeonpyeong near the tense Yellow Sea border, damaging dozens of houses and sending plumes of thick smoke into the air, YTN television reported.
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UPDATE:
Nov 23 (Reuters) - South Korea said it was conducting regular military drills off the west coast before North Korea started firing dozens of shells, but that its firing exercises did not aim to the North.

"We were conducting usual military drills and our test shots were aimed toward the west, not the north," a South Korean military official said.

North Korea said on Tuesday that Seoul had initiated firing of shells, prompting it to take an instant military action.