Yenagoa - Three Dutch nationals were kidnapped in Nigeria's oil producing region while on their way to inspect a hospital built by US oil giant Chevron, the military said Monday.
Scores of foreigners have been abducted in the southern Niger Delta region, home to Africa's largest oil industry, with many release on payment of a ransom.
Mustapha Anka, the military spokesman in the Niger Delta, said two men and a woman from the Netherlands were abducted on Sunday in the Ekeremor area of Bayelsa state.
"They went to inspect a hospital built by Chevron with an NGO. They were not guarded by anybody," he added.
Employees of foreign oil companies are required to have an armed escort when travelling in the Delta, but international journalists, aid workers and others typically avoid taking a security detail.
Dutch foreign ministry spokeswoman Joanne Doornewaard confirmed the nationality of the hostages.
Judith Oosting of the printing company Gerrits&Leffers said two of its employees were among those abducted and that the pair were in Nigeria to help Niger Delta peace activists publish a magazine.
Anglo-Dutch oil giant Shell has had a major presence in the region for decades, with its operations highly criticised over environmental degradation and close collaboration with the military dictators who led Nigeria through much of the 1980s and 1990s.
The kidnappings came as Nigeria's capital Abuja prepared to host a World Economic Forum summit, with business and world leaders including Chinese Premier Li Keqiang expected to attend.
The delta, which churns out roughly two million barrels of crude each day, has seen years of unrest.
The violence eased after a 2009 amnesty deal with rebels in the region. But crime remains widespread, including massive oil theft and ransom kidnappings.
Niger Delta residents have largely not benefited from the huge revenues generated by Nigeria's oil industry, which have been squandered through corruption, while thousands of crude-related spills have devastated the environment.
Anka said there had not yet been any communication with the attackers and so it was not yet clear if ransom was the motivation for the kidnapping.
"Reports indicate they were taken to a forest within that same area (Ekeremor) and the security agencies are responding," he said.
The Niger Delta amnesty programme, which is set to expire in 2015, included massive payouts to militant leaders.
Analysts have voiced concern over worsening unrest in the region if the government does not pledge to extend the payouts.