The American head of a Niger Delta peace organization and two German filmmakers are being detained in Nigeria by State Security on suspicion of what officials are calling espionage and terrorism. The three were involved in the early stages of a documentary about the oil-rich and violence-plagued region when they were arrested. Kari Barber has more from VOA's West Africa bureau in Dakar.

The spokesman for Nigeria's State Security Service, Ado Muazu, says security officials are continuing to look into those arrested, German nationals Florian Alexander Opitz and Andy Lehmann and American aid worker Judith Asuni.

"This woman is still in our custody, the investigation is still on," he said.

Security officials say the two Germans were filming masked youths in the militant-plagued creeks of the Niger Delta when they were apprehended for filming without government clearance.

Officials say American aid worker Asuni was arrested later for her role in helping the Germans and trying to secure their release.

Asuni has lived in Nigeria for decades and heads Academic Associates PeaceWorks, an organization that mediates between militant groups and the government and encourages disarmament.

In an interview with VOA in May, Asuni spoke from her Port Hartcourt office about her work helping militants turn their lives around.

"You have to get yourself a house, you have to get yourself a job, you have to take care of your medical expenses," she said.  "These are all heavy burdens when you are used to being a group member where all of your needs are taken care of. So teaching people how to stand on their own and be independent is very difficult."

Security officials say Asuni was trying to exploit the problems of the Niger Delta.

Nigeria is the biggest oil producing country in Africa, but most people remain in abject poverty. Militant groups, who have been staging a growing number of attacks on oil facilities and kidnapping foreigners, say they are fighting for a greater share of the oil revenue.

One of Asuni's peace workers, who asked not to be named for safety reasons, says Asuni had been working closely with security officials in efforts to broker peace, but he says some in the government were becoming uncomfortable with her work.

Port Harcourt journalist Ibiba Don Pedro says international media, such as the detained German filmmakers, are playing a crucial role in getting information out about the region's problems.

"People should keep coming from outside the country so that the world will know what is happening," he said.

A spokesman for the United States Embassy in Abuja says the U.S. officials are in touch with Nigerian authorities about Asuni's detention.

Meanwhile, Germany's ambassador to Nigeria has rejected charges that the detained Germans are spies and insists they are journalists.

The most well known militant group, the Movement for the Emancipation of the Niger Delta, announced on Sunday it would resume attacks following a period of truce with the Nigerian government after the May inauguration of President Umaru Yar'Adua.