North Korea has detained a South Korean fishing boat missing in the Sea of Japan. Coastguard officials said the crew of the Daeseung was being investigated by North Korean authorities.Earlier, South Korea reported that the boat, 55 Daeseung, with four South Korean and three Chinese sailors onboard, lost communication contact on waters about 270 kilometres off east coast of the North. The boat, in the last contact, said it was moving toward Sungjin Port of the North. In a statement, the South Korean coastguard said its fishing vessel was being investigated by North Korean officials in the presumed North Korea exclusive economic waters in the northern East Sea. According to Yonhap News Agency, the South Korean government hoped the North can take measures in line with the international law and conventions, and allow the boat return as soon as possible.