A Norwegian tanker has been hijacked by pirates off the coast of Madagascar an area not previously thought to be at risk of pirate attack activity. The tanker which was carrying fuel oil and a crew of 21 was travelling from the United Arab Emirates to the Tanzanian port of Dar es Salaam when it was attacked.<br/><br/> Piracy has made the seas off the Horn of Africa among the most dangerous in the world, despite naval patrols.<br/><br/> An international naval force is patrolling the Gulf of Aden and the Indian Ocean but has been unable to stop attacks on shipping from pirates based in Somalia.