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North Korea lobs shells near disputed sea border

SEOUL — The North Korean military fired dozens of artillery shells Tuesday near a disputed western sea border with South Korea, prompting thousands of South Korean islanders to flee to shelters.

Earlier Tuesday, North Korea told the South that it had designated two firing zones near the Northern Limit Line, which South Korea defends as a western sea demarcation line. North Korea claims a border line farther south.

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North Korea subsequently fired about 50 rounds of artillery, but none were believed to have fallen south of the disputed maritime border.

The waters around the disputed sea border remain the most volatile section of the inter-Korean frontier and have been the scene of several naval skirmishes between the two Koreas in recent years. South Korea’s military increased its vigilance Tuesday.

North Korea conducted similar drills in the region on March 31, firing more than 500 rounds of artillery and rockets. South Korean marines fired back, lobbing 300 rounds of artillery north of the line.

North Korea’s live-fire drills followed its harsh criticism of a summit between President Obama and his South Korean counterpart, Park Geun-hye, in Seoul on Friday. After their meeting, the two leaders pledged to impose more sanctions if the North conducted another nuclear test. They also promised to pressure the North Korean government over its human rights abuses.

On Sunday, the North lashed out, calling Park “a dirty prostitute” in thrall to the “pimp” Obama.

South Korean officials and US think tanks have reported increased activities at an underground nuclear test site in Punggye-ri in North Korea.

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