An oil tanker hijacked for a week off Angola last month has been returned to the authorities, but not before hijackers managed to siphon $8 million worth of diesel fuel from the ship for sale on the black market.

The Liberian-flagged vessel, MT Kerala, was chartered by Angola’s state-run Sonangol oil and was stocked with oil for delivery to its trading partners when it was hijacked by pirates off the coast of capital Luanda in late January, disappearing for a week.

Initially, the government suspected the crew of disabling the vessel’s communications system to stage a pirate attack, with Angola Navy spokesman Augusto Lourenco stating that the attack was “faked, and there have been no acts of piracy in Angolan waters.

While details are still emerging in an ongoing investigation, the owner of the vessel, Dynacom Tankers Management of Greece, confirmed that pirates hijacked the ship and made away with $8 million in cargo, wounding one crew member in the process.

Interpol, the Naval Criminal Investigative Service (NCIS) and the Liberian flag operators are now involved in the investigation.

Sonangol board member Anabela Fonseca told a news conference that the vessel had been intercepted by the Nigerian navy on the coast of the Gulf of Guinea.

“The MT Kerala was found in Nigerian waters, but as the coast there did not offer security it was taken to Ghanaian waters and then recovered with help from both countries’ authorities and brought to Luanda,” she said.

Fonseca said the company managed to recover around 78% of the cargo, but that the hijackers managed to transfer about 12,000 tons of diesel fuel, worth some $8 million, before the ship could be intercepted.

The incident raised concerns that piracy is spreading south from the Gulf of Guinea, near Africa's biggest oil producer Nigeria, where most hijacking gangs originate. Angola is the Africa’s second-biggest crude operator and almost all of its production is offshore. It is also one of the most promising emerging oil venues in the region, so the specter of piracy looms large for investors and shareholders.

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