Graphic: the taking of a tanker

Pirates have seized the biggest booty ever taken on the high seas, capturing a fully laden Saudi oil supertanker and its multinational crew, among them two British merchant seamen.

The Sirius Star – three times the size of an aircraft carrier and carrying its full complement of two million barrels of crude oil worth at least $100 million (£67 million) – was hijacked in the early hours of Sunday 450 nautical miles southeast of Mombasa in Kenya, according to the US Fifth Fleet.

“This is unprecedented,” Lieutenant Nathan Christensen, spokesman for the fleet, said yesterday. “It’s the largest ship that we’ve seen pirated.”

Last night the Sirius Star was heading towards Eyl, a notorious pirate haven on the Somali coast, raising fears of an environmental catastrophe if the pirates run aground in waters far too shallow for the vast supertanker.

Shipping analysts said that the cost of sending freight around the world would rise after the attack as a result of higher insurance premiums and an increase in charter rates.

The Sirius Star is the latest of more than 60 vessels to be captured off the Somali coast this year, but the first supertanker. Jitters over the ease with which pirates seized crude equivalent to a quarter of Saudi Arabia’s daily output sent falling oil prices into reverse. They finished up one dollar per barrel.

Odfjell, one of the largest shipping groups in the world, responded to the attack by suspending its routes through the Gulf of Aden in favour of the longer journey around the Cape of Good Hope at the tip of South Africa, raising the prospect that one of the world’s busiest trade routes could be sidelined unless global action is taken to combat the pirate menace.

Britain leads a multinational task force in the area. Last week the Royal Navy was drawn into a shoot-out with a gang attempting to hijack a cargo ship, killing two of the pirates.

But the capture of the Sirius Star hundreds of miles to the south in the Indian Ocean, as it was heading to the US via the Cape, suggests that the Gulf pirates are simply moving into unpatrolled waters or that other pirate groups, recently dormant, have been reawakened.

The supertanker had avoided the Gulf of Aden and the Suez Canal because it is too big to pass through the canal. It is not only the largest ship to be captured but the farthest from the Somali shoreline.

The US Fifth Fleet declined to say whether military action was being considered to rescue the tanker, which is manned by 23 crew from Croatia, the Philippines, Poland and Saudi Arabia in addition to the two Britons.

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