The Nigerian navy killed 12 pirates in a gun battle as they tried to flee from a fuel tanker they hijacked off the coast of the Gulf of Guinea last week, the navy said on Monday.
Pirates took control of the St. Kitts and Nevis-flagged MT Notre on Aug. 15, but an emergency signal was sent to the navy and several gunships were deployed to recover the vessel, Navy Flag Officer Rear Admiral Sidi-Ali Hassan told reporters.
Navy gunships caught up with the vessel and forced it into Nigerian waters but while negotiating the ship's release, the pirates tried to escape on a speed boat. The navy boats pursued but were fired upon by the hijackers.
"The gun battle lasted for about 30 minutes after which they were overpowered. On taking over the speed boat, four of the militants were alive and unhurt while the rest of the pirates were killed in the crossfire," Sidi-Ali Hussan said.
The crew were all rescued unharmed from the MT Notre, which was carrying 17,000 metric tonnes of gasoline, he said.
Pirate attacks off West Africa's mineral-rich coastline have almost doubled from last year and threaten to jeopardise the shipping of commodities from the region. They have already jacked up insurance costs.
It is rare for the navy to engage pirates in gun battles offshore, as vessels are usually released after being robbed of cargo and valuables. Sometimes crew are kidnapped for ransom.