Gunmen in speed boats kidnapped several oil workers in a raid on a ship off the Nigerian coast on Wednesday, industry and security sources said.
Foreigners were believed to be among the hostages because the deep water vessel, operated by Italian oil company Saipem, a unit of ENI , was staffed mostly by expatriates, one source said.
The exact number of hostages was not immediately known.
“Some armed men came in several boats this morning to a facility in deep water and took everyone hostage,” said a security source in the oil industry, asking not to be named.
“Right now the entire facility is under siege and several expats have been taken.”
Dozens of mostly foreign oil workers have been kidnapped in Nigeria this year as ransom-seekers have taken advantage of instability caused by growing militancy in the West African country’s deep south.
Almost all have been released unharmed after payments, although one Nigerian oil worker was killed in August by troops during an attempt to free him.
Kidnapping is just one expression of a deteriorating situation in the Niger Delta, a vast wetlands region that is home to all of Nigeria’s petroleum resources.
Africa’s top oil producer has been forced to cut output by a fifth since February when militants fighting for regional control of the delta’s oil wealth staged a series of attacks on pipelines, platforms and export terminals.
Militancy is fuelled by poverty in villages that have seen few benefits from decades of oil extraction that has yielded huge revenues for the faraway federal government and oil firms.
But the violence has taken on a life of its own, with theft of crude oil and communal flare-ups also commonplace.
Disruption to oil exports from Nigeria helped drive world prices to record highs earlier this year, and analysts expect the situation to get worse as national elections approach in April.