DUBAI (Reuters) - An Iranian vessel with 19 sailors on board has been seized near a Yemeni island by local fishermen, Yemen s prime minister said on Saturday. There was no immediate official Iranian reaction to the comments made by Ahmed Obeid bin Daghr on his Twitter account in which he said the ship was detained off the coast of Socotra, the largest island in an archipelago south of Yemen.  He thanked the fishermen of another island in the archipelago, Abd al-Kuri, which lies to the east of Somalia. Iran s semi-official Fars news agency said that the Yemeni government, which Tehran does not recognize, had  claimed  that an Iranian vessel with a crew of 19 had been seized on Friday. There were no further details on the ship or its cargo. Regional and Western sources have said that Iran is sending advanced weapons and military advisers to Yemen s rebel Houthi movement, stepping up support for its Shi ite ally in the country s civil war. Iran rejects accusations from Saudi Arabia that it is giving financial and military support to the Houthis, blaming the crisis on Riyadh. 