Gunmen have attacked a barge belonging to an oil services company off the coast of Nigeria, kidnapping four foreigners and killing two Nigerian sailors, the country's navy has said.
"Four expatriates are reported to have been kidnapped from the vessel. Two sailors were killed," Commodore Kabir Aliyu, a navy spokesperson, said on Saturday.
He said those kidnapped were from Indonesia, Iran, Malaysia and Thailand. The attack took place at roughly 35 nautical miles off Nigeria's oil rich coastal area in the Gulf of Guinea, the navy and the company said.
The gunmen stormed the vessel in the Gulf of Guinea that belongs to the Sea Trucks Group, Corrie van Kessel, company spokeswoman told the AFP news agency, who confirmed that four of the firm's employees were taken in the raid.
"At this time Sea Trucks Group is making every effort to ascertain the whereabouts of its personnel," she said.
Six naval personnel - all Nigerians - were providing security aboard the vessel, which belongs to the Sea Truck oil services company.
The Nigerian navy has dispatched a boat and a helicopter to the area.
The International Maritime Bureau (IMB) said in a report released last month that there had been 32 piracy incidents recorded off the coasts of Benin, Nigeria and Togo in the first half of 2012, up from the 25 attacks in 2011.
An IMB official told AFP that armed assaults on vessels in the area had been under-reported for several years. Many of the raids have involved "high levels of violence," the report further said.
Van Kessel explained that Sea Trucks Group was heavily involved in the oil and gas sector in the Delta, but declined to comment on the specific activities of the fired-on ship.
She further said that two of the company's vessels came under attack, although the navy insisted only one ship was involved.
Most of the world's leading oil companies operate in Nigeria, Africa's top oil producer and the world's eighth largest.
Production in the region had for several years been curbed by the Movement for the Emancipation of the Niger Delta, but a 2009 amnesty deal greatly reduced the unrest and crude output has since recovered.
On Friday, Nigeria said oil production had hit its highest level ever, reaching 2.7 million barrels per day.