Malaysia-flagged containership Albedohas sunk after being held by pirates for more than two years, and the fate of its 15 remaining crew is unconfirmed.
Albedo was the last large vessel in Somali pirate hands and its crew endured a lengthy incarceration after the 1,066 teu boxship was captured in November 2010 in the Indian Ocean.
EU Navfor confirmed the ship, owned by Majestic Enrich Shipping, remained under pirate control when it sank.
A warship and maritime patrol aircraft have closed the sea area and are carrying out a search and rescue operation to look for any survivors.
Although the whereabouts of the crew are not known, an EU Navfor spokeswoman has reported sightings of a liferaft and a beached lifeboat.
Albedo was hijacked with 23 crew on board. In August last year, seven Pakistani hostages were released after a family-led campaign raised a $1.2m ransom.
One Indian seafarer is understood to have died of cholera while held captive.
The only other ship held by pirates is Oman-flagged fishing vessel Naham III. Pirates seized the vessel in March 2012, taking 28 people hostage.
For more maritime news see Lloyd’s List