Armed tribesmen have kidnapped a Norwegian national in the Yemeni capital Sana'a and taken him to the eastern province of Mareb, a security source was quoted by dpa as saying on Sunday. They are demanding the release from prison of one of their loyalists, and are in talks with the interior ministry, the source said. The ministry was expected to comply with their demand, the source added, but he could not say when the Norwegian could be released.