LAGOS Gunmen in Nigeria released eight foreign oil workers seized from a vessel off the Niger Delta on Saturday but eight other people abducted in separate incidents were still being held, security officials said.
The eight Russian, Latvian and Lithuanian men were seized early on Saturday from a liquefied petroleum gas (LPG) tanker off the mouth of the Bonny river in the delta, a network of mangrove creeks which is home to Africa's biggest oil industry.
Lieutenant-Colonel Sagir Musa, military spokesman in the eastern Niger Delta, said the eight had been voluntarily released by their captors.
"They have been released late this evening ... I doubt that any ransom was paid," Musa said, without giving further details.
Private security contractors said the men were thought to have been working for Global Gas and Refining Ltd, a Nigerian subsidiary of U.S.-based Global Energy Inc. run by a prominent local businessman, which may have aided their rapid release.
The company could not immediately be reached for comment.
Insecurity in the world's eighth biggest oil exporter has cut Nigeria's oil output by around a fifth since militants launched a campaign of violent sabotage in early 2006 to press for greater development in their neglected communities.
Despite half a century of oil extraction, most villagers in the Niger Delta remain mired in poverty, while the industry has polluted their land and water.
"ALL IS FAIR IN WAR"
Criminal gangs have taken advantage of the breakdown of law and order, funding themselves through a lucrative trade in stolen crude oil and by kidnapping businessmen, local politicians and expatriates for ransom.
More than 200 foreigners have been seized since the militants began their campaign more than two years ago. Almost all have been released unharmed.
In an attack late on Thursday, gunmen took 11 Russians and a Ukrainian on a vessel off Bonny Island. Some were released on Friday but five were still being held, security officials said.
More than a dozen men in speedboats kidnapped two oil engineers, one from the Philippines and one Nigerian, from a vessel in the main industry hub of Port Harcourt on Friday. Another Filipino was seized while buying food on land.
Security sources said it was not clear whether the same group was behind all the kidnappings. No ransom demands have been made publicly.
Two Germans working for construction firm Julius Berger kidnapped two weeks ago are also still being held.
The Movement for the Emancipation of the Niger Delta (MEND) -- the region's main militant group which has pledged to bomb oil pipelines over the next few weeks -- said it was not involved in any of the abductions.
"None of our units have reported being involved in any kidnapping yet," MEND said in an e-mail to Reuters, but said the insecurity would help its campaign.
"These gangs have their advantages even though we do not support their motives and sometimes the modus. The truth is that all is fair in war, as they have a way of frustrating the military and helping them lose focus," it said.
(Additional reporting by Austin Ekeinde in Port Harcourt and Randy Fabi in Abuja; editing by Richard Williams)