North Korean coast guards intercepted a Russian yacht in neutral waters and escorted it to a N. Korean port without giving an explanation on Friday. The Russian embassy in Pyongyang has demanded the immediate release of the Russian vessel and its crew.

Sportsmen aboard the Elfin yacht were returning to Vladivostok from an international regatta in the South Korean port of Busan, when it was waylaid by what had appeared to be a fishing boat sailing under the North Korean flag.

The incident occurred some 85 nautical miles off the shores of North Korea at 19:25 local time (10:25 GMT). According to Vesti Primorye, the captain of the Russian vessel, Dmitry Nazarov, was forced to board the North Korean vessel, while three (or four) other members of the crew locked themselves inside the yacht.

The North Korean ship took the Russian yacht in tow and brought it to the port of Kimchaek. Later there was a report that a North Korean coast guard vessel had detained the Russian vessel.

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Russia’s Emergency Ministry was informed of the incident at 20:00 local time. The Russian embassy in Pyongyang learnt about it at about 21:00 and immediately asked the North Korean authorities for clarification.

“According to available information, the yacht is in the port of Kimchaek, the captain and crew are safe and sound,” Interfax cited the embassy’s public relations officer Denis Samsonov as saying.

The Russian consul general in the region, Yury Bochhkarev, has contacted authorities in Hamgyong Province, but has not been granted permission to meet the detained Russian citizens so far.

The Russian embassy has demanded explanations from Pyongyang and expects North Korean authorities to present detailed information on the incident by the end of Saturday.

The vice-president of Russia’s Primorye Yachting Sport Federation, Evgeny Khromchenko, told RIA Novosti the crew had contacted their relatives by phone and explained the situation.

According to Khromchenko, the captain of the Elfin is an experienced sailor and was guiding his vessel within the allowed lane. Captain Nazarov has passed the same route “dozens of times,” Khromchenko said, noting that this is not the first incident of its kind.

“They will be detained for two-three days,” he said, adding that the North Koreans act unlawfully, “like pirates,” trying to extort money. They usually damage yachts in the process.

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Russian yachtsmen could be held accountable for “violating” North Korea’s rules regarding approaching national territorial waters, Petr Osichansky, the head of Maritime Incidents Investigative Center, told RIA Novosti.

“North Korea has harsh regulations when it comes to their territorial waters, you cannot approach them closer than 50 (nautical) miles. The yacht likely violated that rule,” Osichansky told RIA Novosti. He explained that for the rest of the world territorial water zones are always 12 miles.

This “violation” is not a severe one, particularly when it comes to Russian sailors, so they will be released soon, Osichansky said. He added the incident is definitely not the first one, and previous ones ended amicably.

North Korea established its 200-mile maritime economic zone in 1977.