Somali pirates have hijacked a Yemeni cargo ship in the Gulf of Aden.
Andrew Mwangura, head of the East African Seafarers Assistance Programme, identified the vessel as the MV Amani but provided no further details.
Another maritime official speaking on condition of anonymity said the ship had been seized last week.
World powers have vowed tough action against rampant piracy off Somalia's coastline, which has disrupted commercial traffic in the Gulf of Aden, a major world maritime trade route.
On 15 November the largest ship ever seized by pirates in the region was hijacked in the Indian Ocean.
Pirates have demanded a ransom of between $15m and $25m for the release of the Saudi-owned Sirius Star, with a cargo of 2m barrels of crude oil and a crew of 25.
Somali pirates currently hold at least 17 ships and more than 250 crew.
