A British oil worker has been kidnapped in Nigeria, the Foreign Office said.
One report says the man was seized from the Bulford Dolphin rig
The man was kidnapped in the early hours of Saturday off the coast of the Bayelsa state, in southern Nigeria.
A Foreign Office spokesman said: "We are in contact with the Nigerian authorities to try to bring this to a swift and peaceful conclusion."
One unconfirmed report said the worker, who has not been named, was kidnapped from the Bulford Dolphin rig, 40 miles off the Niger Delta.
Six Britons, one American and a Canadian were kidnapped from the Bulford Dolphin rig last June and were released two days later.
The Niger Delta, which accounts for all of Nigeria's crude exports, has been hit by a wave of abductions and attacks on oil facilities since 2005.
The militants want oil companies to negotiate on a range of issues affecting local people, who see little benefit from the oil industry.
Issues they want addressing include employment for local people and the environmental impact of drilling, industry analysts said.
An upsurge of attacks on foreign oil interests has cut Nigeria's oil production by around 25%.