One Briton and one American taken hostage in Nigeria have been released after five days in captivity.
A security source put the number of suspected fighters killed at two.
“It is the first significant success of the navy,” he said.
On October 10, villagers from the Oporoma community seized 60 oil workers at a nearby pumping station. The workers were released after two days.
Poorly paid and ill-equipped, Nigerian security forces often abandon their posts when oil facilities are attacked. They are usually outgunned and outnumbered by their attackers.
About 600,000 barrels of oil a day are being prevented from leavng Nigeria since militant attacks in neighbouring Delta state in February.
Another oil production facility at Tebidaba in Bayelsa has been under siege since November 6, reducing output there by 50,000 barrels a day.
About 40 workers of Italian oil company Agip are currently being held on the platform while their captors discuss demands for oil-spill compensation with the local government.