Somali pirates on Wednesday hijacked the Russia-owned oil tanker MV Moscow University bound for China 350 miles off the coast of Yemen with 23 Russian crew and crude oil worth $52 million on board.
"The oil is Chinese. It belongs to Unipec. It was sailing to (the Chinese) port Ningbo," said a Russian shipping source.
Maritime experts said the tanker had a deadweight of 106,474 tonnes and a Russian shipping source said the vessel had begun its journey from Sudan with a cargo of 86,000 tonnes of oil.
"This morning we had an attack on a Liberian flagged ship Moscow University in the north eastern horn of our operation," EU Navfor Commander Rear Admiral Jan Thornqvist told reporters in the Kenyan port city of Mombasa.
"The crew members locked themselves in the radar room. This ship has been hijacked."
Somali sea bandits continue to outwit an international fleet of warships in the busy shipping lane linking Europe with Asia, raking in tens of millions of dollars in ransoms.
A source at the Novorossiyk Shipping Company which owns the tanker said "the tanker was sailing from Sudan to China".
Oil tankers are sailing further east into the Indian Ocean away from Somalia's coastline to avoid pirates who are striking deeper out at sea, shipping experts say.
Some shipping companies are re-routing vessels around the southern tip of Africa to avoid the Suez Canal and pirate-infested Gulf of Aden, adding weeks to passage times and substantial expense. But many continue to run the gauntlet through the busy Gulf of Aden shipping lanes where warships operate convoys and have set up transit corridors.
EU Navfor said the MV Moscow University had not registered with the Maritime Security Centre Horn of Africa for its transit through the Gulf of Aden.
The Russian shipping company said on its website that the Russian warship Marshal Shaposhnikov, which has been patrolling the dangerous waters, was on its way to the tanker.
The use of mother ships has enabled Somali pirates to strike as far as the Mozambique Channel and off India's coast in recent months, launching smaller boats known as skiffs against ships.
An estimated 7 percent of world oil consumption passes through the Gulf of Aden.
Better weather is expected to enhance opportunities for attacks in the coming weeks.