Story highlights About 30 soldiers fired "several hundred shots," a military official says

The man ignored repeated warnings to turn back, he says

The man jumped into the Imjin River at the border with a float and began swimming

Attempts to defect from South Korea to the North are rare

A man who tried to swim across a river to North Korea was killed by a rain of bullets fired at him by South Korean soldiers, a military official said.

The shooting took place Monday afternoon at the heavily fortified border that separates the two Koreas.

The South Korean man managed to get past a barbed wire fence by the bank of the Imjin River, which flows through part of the Demilitarized Zone between the two countries, and then jumped into the water with a Styrofoam float, Brig. Gen. Cho Jong-sul said Tuesday.

"We kept warning him verbally to come back to land," Cho said at a news conference. "The river was only about 800 meters wide where he jumped in. It wouldn't have taken long for him to swim across with the float. It was a very tense situation."

When the man failed to heed the warnings, the entire unit of about 30 soldiers began firing at him.

"Several hundred shots were fired," Cho said.

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Asked whether this was a reasonable response, he said, "It is a regulation to shoot anyone who does not respond to the command and tries to escape in the controlled area."

Defections to North unusual

The two Koreas are technically still at war after the all-out conflict they fought between 1950 and 1953 ended in a truce rather than a peace treaty. Their border is considered to be the most heavily fortified in the world.

Authorities said the man's surname was Nam but declined to disclose any other details about him beyond his nationality. The case is still being investigated, Cho said.

Several South Korean news outlets reported that Nam was in his 40s.

While tens of thousands of people have managed to flee to South Korea from the authoritarian regime in the North -- mostly through China -- defections in the other direction are very rare.

Cho didn't say whether there had been any similar cases previously. The South Korean news agency Yonhap reported that this was the first shooting of this kind of somebody apparently trying to defect to North Korea.

In 2009, the North's state-run Korean Central News Agency trumpeted the defection of a South Korean, Kang Tong-rim, who it said crossed the eastern part of the border. But South Korean authorities said he was fleeing police who wanted him for an assault incident.