ABIDJAN (Reuters) - Suspected Nigerian pirates have hijacked a French-owned Luxembourg-flagged tanker along with its 17-member crew off Ivory Coast, Ivorian officials and the International Maritime Bureau said on Monday.
The Gulf of Guinea area is second only to the waters off Somalia for piracy and there has been a spate of violent attacks in vessels in recent days, prompting the bureau to issue a security alert for the region.
The Gascogne was the second vessel to be seized off Ivory Coast in less than three weeks and the first to have been taken so far from shore.
Many of the pirate gangs are offshoots of militant groups that once operated in Nigeria's oil-rich Niger Delta and mainly target ships carrying refined petroleum products that are easily sold on the local black market.
Ivory Coast authorities said the Gascogne had been chartered by South Korean petroleum transporter SK Shipping. It had taken on 3,000 tonnes of diesel fuel in Abidjan on January 30 but had already off loaded a portion of its cargo when it was seized on Sunday.
The 17-strong crew comprised seven Togolese, two Senegalese, two Ivorians, one South Korean, one Chinese and four sailors from Benin, said Bertin Koffi Tano, Ivory Coast's head of maritime and port affairs.
"The ship was indeed hijacked in Ivorian waters," Tano said, adding that the IMB, a division of the International Chamber Of Commerce charged with fighting maritime crime, was tracking the Gascogne off the coast of Nigeria on Monday.
"We don't know who (the attackers) are. We don't know what kind of weapons they have ... We don't have the means to keep a watch over Ivorian territorial waters," he said.
The IMB's Live Piracy Report said the Gascogne was sailing 70 nautical miles (130 km or 80 miles) south of Ivory Coast's commercial capital Abidjan when it went missing.
SEA-Tankers, the ship's French owner, said it lost contact with the vessel on Sunday morning.
Three tanker vessels have been targeted in attacks in the Gulf of Guinea in the past five days. The two other incidents occurred off the coast of Nigeria, with one attempted hijacking claiming the life of a crew member early on Monday.
While attacks in the waters off Nigeria, Togo and Benin have been commonplace for years, increased cooperation between national authorities and more robust policing of territorial waters have had some success.
However, analysts believe these efforts may be driving Nigerian pirates to operate further from their home waters off countries, such as Ivory Coast, with poorly equipped and trained navies and coastguards.
Ivory Coast recorded its first vessel hijacking last October when suspected Nigerian pirates seized a Bahamas-flagged tanker carrying more than 32,000 metric tonnes of gasoline near Abidjan's port. The 24 crew were later freed unharmed.
Gunmen attempted, but failed, to seize a ship anchored off Abidjan's port in December, and last month pirates took control of a tanker carrying 5,000 tonnes of fuel as it waited to unload its cargo at Abidjan's tanker terminal.
"It appears that the Nigerian pirates are spreading. All of these vessels were tankers carrying gas oil. They're all taken back to Nigeria to siphon off the oil, then the crews are freed," Noel Choong, head of the IMB's piracy reports division based in Malaysia, said.
"This whole process takes about five or six days."
Additional reporting by Loucoumane Coulibaly in Abidjan, Robert-Jan Bartunek in Brussels and Michel Rose in Paris; Editing by Alison Williams