A Russian yacht has been detained by North Korean coastguards in the Sea of Japan and towed in to land with five crew members on board, Russian officials said Saturday.

"The North Korean side has communicated that the yacht has been taken to the port of Kimchaek," Igor Agafonov, a foreign ministry official in Russia's far-eastern city of Vladivostok told state-run RIA Novosti news agency.

"The crew is alive and well. We are still waiting for an explanation from North Korea as to the reasons for the detention," Agafonov said, adding that diplomats were seeking permission to visit the crew.

Earlier an unnamed official at the Russian embassy in Pyongyang told TASS news agency that the sailboat Elfin was detained by North Korean coastguards late Friday with five people on board as it was sailing from a competition in the South Korean port of Busan to Vladivostok.

"The embassy... has handed over a note to the North Korean side demanding the immediate release of the crew," Denis Samsonov, a spokesman for the Russian mission in North Korea, told RIA Novosti.

On Friday the vice president of the regional sailing federation Yevgeny Khromchenko wrote on Facebook that the vessel had been stopped by "North Korean fishermen" 85 nautical miles (160 kilometres) from shore and was being towed in to land.

Russia shares a short land border with North Korea and enjoys relatively friendly ties with the country's reclusive Stalinist regime.

Russia's Foreign Affairs Ministry confirmed in a statement that the yacht was sailing from the South Korean port of Busan towards Vladivostok when it was boarded and searched on Friday evening.

"A note was sent to the North Korean side in order to find out the reasons for this detention. The Consul General of Russia... is waiting for permission to meet the crew," the statement said, adding that the crew were not in danger.