The wife of a UK oil worker feared dead after being taken hostage says she is "ecstatic" at news he has been freed.
Militants have disrupted oil production in the delta
Paul Smith, 30, from Peterhead, Aberdeenshire, was among seven men released 18 days after being seized by gunmen at a compound in Nigeria.
His wife, Paula, said she had been told the father-of-two was dead and could not believe it was him on the phone.
The seven oil workers, among them three other Britons, are all said to be in good health after their release.
A Romanian, a Malaysian and an Indonesian were also among the group kidnapped on 3 October at Nancy's Bar in the compound in Eket, in Akwa Ibom state on the Niger Delta.
The other Britons have been named as George Mclean, 43, from Elgin, father-of-three Sandy Cruden, from Inverurie, and Graeme Buchan, also from north-east Scotland.
The men have been sent to Port Harcourt in neighbouring Rivers state to be released to their various companies.
A number of Nigerian security guards were killed when armed men raided the compound. Mr Smith was wrongly reported to have died in captivity.
Speaking from her home in Aberdeenshire, Mrs Smith said: "We've just had the brilliant news, they're all safe and well.
"I've spoken to him, he's in Port Harcourt. He told me that he had been released and everything is fine.
The men were seized at the compound in Eket
"I was told that he was dead. I'm just ecstatic, I couldn't believe it was him on the phone. There's no words to explain how we feel right now."
A spokesman for Exxon Mobil said the firm was pleased the situation had been resolved.
The men were employed by Aberdeen-based Sparrow Offshore and Texas-based Oceaneering International.
Malcolm Wilson, chief operating officer at Sparrows Offshore Ltd, said: "Our men are coming home.
"I'm delighted to tell you that the intensive efforts by the governments and companies involved have been successful in securing the safe release of the three Sparrows employees and those of other companies who were taken hostage in Nigeria 18 days ago."
Mr Wilson added: "We have spoken to the men and they are in good spirits, but we have arranged medical checks as a routine precaution before they fly back to the UK."
Mr Wilson said his firm would not be giving details of communications between government officials and the group which captured the men.
Police said they had no information of the terms of their release.
Despite official denials, in most cases some sort of financial deal is struck with the kidnappers.
Hostage-taking has become a lucrative business for armed groups in the Niger Delta - an area of creeks and swamps about the size of Scotland.
The latest kidnappings come despite Nigeria's President, Olusegun Obasanjo, promise in September to take strong action to curb the armed groups.
The BBC's correspondent in Lagos, Alex Last, said the problem was likely to get worse in the run-up to Nigeria's elections next year as rival politicians hope to use the armed groups in their battles to win power.