Last week, we explained why piracy has shifted from Africa’s east coast to its west. In short: higher security near Somalia combined with a new strategy near Nigeria. In at least one hijacking, pirates sought a tanker’s cargo of oil instead of ransoms for crew members.

Or, rather, in at least two hijackings. From the AP:

A French-owned oil tanker missing off Ivory Coast with 17 sailors on board likely has been hijacked, an official with an international piracy watchdog said Monday, in what may be the latest attack by criminal gangs targeting the ships to steal their valuable cargo. Meanwhile, a sailor died in a similar attack Monday near Nigeria’s largest city.

Details remained scarce Monday about the fate of the ship, flagged in Luxembourg. The ship had been reported missing Sunday and officials believe it fell victim to the same pirates operating throughout the Gulf of Guinea, said Noel Choong, a spokesman for the International Maritime Bureau in Malaysia.

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Pirates surrender to a U.S. Navy vessel near Somalia in 2011

usnavyPirates surrender to a U.S. Navy vessel near Somalia in 2011.

This is on top of two near misses.

The presumed attack Sunday comes amid a series of escalating attacks in the Gulf of Guinea, which follows the continent’s southward curve from Liberia to Gabon. On Monday, pirates attacked another oil tanker anchored off Nigeria’s largest city, Lagos, shooting one of the crew members, Choong said. The sailor died while in transit to a local hospital, the maritime bureau later said, though offering no other details.

A security detail from the Nigerian navy shot back at the attackers, driving them away, the bureau said. Commodore Kabir Aliyu, a spokesman for Nigeria’s navy, declined to immediately comment about the attack.

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In another attack Thursday off Nigeria’s oil-rich southern delta, pirates on several small boats assaulted another tanker. In a sign of how violent the attacks have grown, the pirates fired a rocket-propelled grenade at the tanker during the onslaught, which missed the ship, the maritime bureau said. The crew suffered no injuries in the attack and their ship escaped, though it sustained damage from the gunfire, the bureau said.

As we’ve mentioned before, some of the region’s oil is headed for America’s East Coast. When pirates plagued the coast of Somalia, corporations hired security teams and the U.S. Navy got involved. It would be very surprising if similar measures weren’t under discussion at Shell and Chevron at this very minute.