Eight hostages - six of them Britons - who were abducted while working on an oil rig in Nigeria are on their way home after being freed.
Numerous armed militia groups operate in the Niger Delta
The eight men, including an American and a Canadian, were seized on Friday from an offshore oil rig in the south of the country.
After arriving in Lagos, Nigeria, the men will return to their own countries.
The incident is the latest in a series of militant actions aimed at oil businesses based in Nigeria.
President Olusegun Obasanjo had joined in the mediation efforts to free the eight men.
National police spokesman Haz Iwendi said the men were freed as a result of negotiations brokered by authorities in Bayelsa state.
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 sources said.
The workers had been on board the drilling rig Bulford Dolphin, which operates for the Nigerian oil company Peak Petroleum.
The rig is operated by Aberdeen-based Dolphin Drilling, which employs six of the men who were taken hostage.
A spokeswoman for the firm said: "We're trying to get them home as quickly as possible".
She said two of the men were from north-east Scotland and two were from England. The other two Britons now live in Spain and Malaysia.
Dolphin Drilling's senior vice president Iain Mitchell said: "We are extremely relieved that the men have been returned safely and thank our client and the Nigerian authorities for their support in resolving the situation quickly."
He also thanked the UK authorities for their support.
The Niger Delta is home to Nigeria's oil industry, but there is widespread poverty.
It is not clear who was behind the action, but the Movement for the Emancipation for the Niger Delta (Mend), the major militant group, has said it was not responsible for the kidnappings.
The rig had sent out a distress call on Friday, saying it was under attack from between 20 and 30 men in speedboats.
The attackers in four boats fired shots into the air before boarding the rig, security sources said.
There were 84 oil workers on the rig when it was attacked.
An upsurge of attacks on foreign oil interests has cut Nigeria's oil production by 25% - a key factor in the high world price of crude oil.