Eight expat oil workers kidnapped from Nigeria rig

LAGOS, June 2 (Reuters) - Gunmen abducted eight foreign workers in a night-time raid on an oil rig off the coast of Nigeria on Friday, raising new security fears after a series of militant attacks that cut output from Africa's top oil producer.

Some 20 to 30 attackers fired shots as they boarded the rig from four speed boats but no one was injured, security sources familiar with the situation said.

"Some unknown persons boarded the rig at 3 a.m. (0200 GMT) and took eight workers. They are six from the UK, one Canadian and one from the U.S.," said an executive from one of the companies that operate the Bulford Dolphin rig. He denied reports that eight Nigerians were also abducted in the attack.

Norwegian oilfield services group Fred. Olsen Energy , which owns the rig, said it had made contact with the abducted men. It also said the kidnappers were seeking negotiations, but gave no details on their identity or demands.

It was not clear if militant group the Movement for the Emancipation of the Niger Delta (MEND) was involved. MEND's attacks have shut down a quarter of Nigeria's 2.4 million barrels per day production of crude oil since February.

The MEND campaign contributed to several spikes in world oil prices. OPEC member Nigeria is the world's eighth-biggest exporter of oil and the fifth largest supplier to the United States, where its sweet, easy-to-refine crude is highly prized.

Bulford Dolphin, leased to Nigerian firm Peak Petroleum which operates it in partnership with Equator Exploration , is an exploration rig 40 miles (64 km) off the coast that is not expected to produce any crude oil for several years.

Fred. Olsen said 84 crew were on the rig at the time of the attack. All but those abducted were safe, and non-essential staff were being evacuated to the oil city of Port Harcourt.

EMBARRASSMENT

The timing of the attack is embarrassing for Nigerian authorities and particularly the navy, which was celebrating its 50th anniversary with an international fleet review by President Olusegun Obasanjo in Lagos on Friday. Senior U.S. and British naval commanders were taking part in the festivities.

The bulk of Nigeria's oil is pumped onshore or in shallow water in the Niger Delta, a vast wetlands region where poverty, a lucrative trade in stolen crude, a breakdown in law and order, and corruption have fuelled militancy and unrest.

As the Niger Delta has become increasingly dangerous, oil companies have moved towards offshore production as deepwater facilities are deemed easier to protect. However, attacks like the one on the Bulford Dolphin rig suggest some local groups are equipped and organised for attacks far from land.

Security sources speculated at first that MEND, which demands greater local control over oil revenues, was behind the kidnappings. But MEND has usually claimed its attacks within minutes and there was no word from the group on Friday.

Another possibility was that the kidnappers were disgruntled members of Niger Delta communities who wanted the oil companies to give them money or fund development projects in their lands, the sources said. Abductions are a common tactic by such groups.

The Bulford Dolphin rig is located in oil exploration block OML 122, which is the subject of an ownership dispute between Peak and oil major Royal Dutch Shell .

A Shell subsidiary said on Thursday it was taking legal action to assert ownership of a 40 percent interest in OML 122 after Peak sought declarations to the effect that Shell's interest had terminated. (Additional reporting by Richard Solem in Oslo and Tume Ahemba in Lagos)