Six Nigerian contractors working for US oil giant ChevronTexaco and two naval officers were kidnapped in two separate incidents today, but four oil workers were later released, authorities said.
The Nigerian navy despatched a warship to the remote area of the Niger delta in the south of the African country to secure the release of the four still in custody.
"We have sent a naval warship to flush out the boys," said Commander Joseph Manusibeya, executive officer at the Warri naval base. It was the latest episode in a low-intensity conflict involving rival ethnic militants, oil companies and troops in the delta where most of the OPEC country's oil is produced.
ChevronTexaco officials in Nigeria declined to comment.
Last week, 21 ChevronTexaco contractors working in Escravos were briefly held by armed ethnic Ijaws who seized four supply barges. All were released.
A local Ijaw leader last week called on ChevronTexaco to halt its operations in the area, which produces Escravos crude oil, until the crisis, mostly over jobs and money, is resolved.
The company has already halted 140,000 barrels per day of onshore oil production at Escravos, equivalent to about a quarter of the total, as a preventive measure to protect employees since political violence erupted in March.
The company still pumps about 350,000 barrels per day of crude oil from offshore wells.