The European Union anti-piracy force says Somali pirates are believed to have hijacked a Vietnamese-owned cargo ship.
The bulk carrier Hoang Son Sun apparently was seized off the coast of Oman. The anti-piracy force said Thursday the ship is carrying 24 crew members, all Vietnamese.
The European agency said the vessel was not registered with maritime authorities who help ships avoid pirate attacks.
Somali pirates have seized at least six ships near Oman since December 25, and they are believed to be holding 30 vessels and more than 700 hostages.
International naval patrols have been unable to stop the pirate gangs, who have received hundreds of millions of dollars in ransom money in recent years.
Some information for this report was provided by AP, AFP and Reuters.