"It apparently failed to reach the runway and fell into the sea, " said Sirait.

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He fell into the sea when he and his parents were walking near the shore.

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Hampshire police said the second boy was also hurt when he fell into the sea.

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The missiles apparently fell harmlessly into the Sea of Japan, and U.S. officials said the long-range Taepodong-2 failed shortly after take-off, calling into question the technological capability of North Korea's feared ballistic missile program.

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"The last time I measured it 15 months ago, the lighthouse was 20.6m (67.5ft) from the sea and my best guess is that it had 10 years before it fell into the waves, " he said.

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