Somali pirates hijacked the Pakistani-flagged fishing vessel MV Shahbaig last Sunday, the European Union naval force said in a statement.
The ship, with a crew of 29 on board thought to be Pakistani, was seized 320 nautical miles east of Socotra, an island off the Horn of Africa, the EU Navfor force statement issued yesterday said.
Pirates currently hold 11 ships and 283 hostages along the coastline of Somalia, according to Navfor, which monitors piracy in Somali waters.
There has been an upsurge in piracy in the Indian Ocean, particularly off the Somali coast and in the Gulf of Aden despite anti-piracy operations by the European Union, NATO and several individual states.
The heavily-armed sea gangs in Somalia have made tens of millions of dollars in ransoms by terrorising commercial shipping.