Eight foreign oil workers kidnapped in Nigeria, including an American, were released Sunday, a local government spokesman said, adding that he was with them in the presence of the governor of a southeast Nigerian state.

"All the hostages have been released. They are with the governor now," said Ekiyor Welson, spokesman for Bayelsa state in the southern Niger Delta region where the eight were kidnapped from an offshore oil rig Friday. He spoke from the state capital, Yenagoa.

CountryWatch: Nigeria

Six Britons, one American and a Canadian were kidnapped from a rig that was drilling off Nigeria's southern coast. The oil rig was operated by Aberdeen, Scotland-based Dolphin Drilling Ltd. for the Nigerian oil company Peak Petroleum.

Confusion surrounded the men's fate earlier Sunday, with a police spokesman first reporting all eight were released then retracting his statement to say the kidnappers had only released two Britons. A presidential spokeswoman had said the other six were expected to be released soon.

Diplomats from the Canadian, British and U.S. embassies in Nigeria could not be reached for comment. In London, officials at Britain's Foreign Office said they were still looking into reports the men had been freed.

Police declined to say whether a ransom was paid and did not say who was responsible for the hostage-taking.

The Movement for the Emancipation for the Niger Delta, the main militant group responsible for a wave of attacks and hostage takings this year in Nigeria's oil-rich southern delta, has said it was not responsible for the kidnappings.

The group, known as MEND, which has kidnapped oil workers in the past as part of a campaign for a better distribution of Nigeria's oil wealth, had said it believed the most recent kidnapping was purely a moneymaking scheme.

Speaking before the hostages' release, Dolphin spokeswoman Sheena Wallace said she did not have the names of the missing crewmen or information about the kidnappers' demands. She said she did not know what group was behind the kidnapping. Local representatives of the company could not be reached for comment.

In recent months, oil-region militants have blown up oil pipelines and kidnapped other foreign workers. MEND has claimed responsibility for two kidnappings and blown up oil installations. The group's actions have cut oil production in the country and helped drive prices higher on international markets.

Presidential spokeswoman Remi Oyo had called the abduction a "misunderstanding" between local communities and the oil company but did not elaborate.

Nigerian militants have justified other such kidnappings as part of their campaign for local control of oil revenues. Other groups have kidnapped oil workers as bargaining chips to prod companies to increase jobs or improve benefits. The kidnappings usually end peacefully.

Last month, an unidentified gunman riding a motorcycle shot and killed an American traveling in a car to work at the offices of the U.S. drilling equipment maker Baker Hughes Inc. in the southern Nigerian oil hub of Port Harcourt.

Nigeria, which normally pumps 2.5 million barrels of crude a day, is the fifth-largest source of oil imports to the United States.