Two British security guards have jumped overboard from a chemical tanker seized by Somali pirates in the Gulf of Arden, reports have said. The men, along with another crew member are then reported to have been picked up by a German naval helicopter. The Liberian registered vessel, which has at least 28 crew, is now thought to be in the control of pirates.The International Maritime Bureau said the the Liberian-flagged tanker was hijacked early on Friday in the Gulf of Aden. The vessel was captured in the same waters where many of the recent hijackings have taken place, the narrow shipping lane between Somalia and Yemen.