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By Jeremy Clarke

NAIROBI, April 21 (Reuters) - A British journalist and Kenyan colleague have been arrested and interviewed by Nairobi anti-terror officers for filming a police station while researching a story on disputed terror arrests.

Dan Edge, 29, and Susan Kurumba, 27, were taken into custody on Friday under suspicion of "terror-related activity" for shooting footage of the outside of Kileleshwa police station in the capital of the east African nation, their companies said.

"The arresting officer completely overreacted by confiscating their tapes and calling the anti-terrorism police," said John Gatibaru, general manager of local production company Vivid Features, which employs Kurumba.

Edge was working for Britain's Channel Four investigative programme "Dispatches", with Kurumba assisting him.

The pair "have got all the relevant required filming permits ... they have got everything they need to be working in the country," a spokeswoman for Channel Four in London said.

Police sources confirmed the arrests but gave no more details.

The journalists were working on a story about the controversial arrest of Islamists in Kenya who fled Somalia earlier this year. Some have been victims of secret detention in Ethiopia with U.S. blessing, human rights groups say.

"They were filming in broad daylight," Gatibaru added of the pair, who spent the night in separate cells.

"They had interviewed the Kenyan foreign minister in the morning and were meant to be interviewing the prime minister of Ethiopia this week, which has now had to be put on hold."

Channel Four were told on Friday the dispute would only take a few minutes to clear up, a media source told Reuters, adding that since the arrests Kenyan cameramen had been filming in and outside the police station where they were being held.

Both Vivid and Channel Four were optimistic the pair would be released late on Saturday. Kenya's anti-terrorism unit has viewed Edge's footage and determined it harmless, Gatibaru said.

But the commissioner in charge of police and security for the Kenya National Commission on Human Rights, Hassan Omar, said it seemed both Edge and Kurumba would be held over the weekend to appear in court on Monday.

Despite repeated calls to police spokesmen, and Kileleshwa station, officers gave no more information on the case.

Considered by Western security services a potential weak flank in the fight against global terrorism, Kenya has been a victim of several major al Qaeda-related attacks.

Those factors have made authorities jumpy in recent times and police are accused of numerous over-hasty arrests, particularly of local Muslims. (Additional reporting by Tim Castle in London)

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