OSLO (AFP) - Norway was the target of an attack allegedly planned by three men suspected of terrorism arrested last week by Norwegian and German police.

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District attorney Signe Kathrine Aalling said the three were planning one or more attacks on Norway, Norwegian news agency NTB reported, adding that they planned to use hydrogen peroxide to make a bomb.

National prosecutor Jan Glent told reporters last week the three suspects were believed to have links to Al-Qaeda and to attempted attacks in New York and Manchester, England.

The three men have only been identified by Norwegian police as a 39-year-old ethnic Uighur from China who is a Norwegian citizen, a 31-year-old asylum-seeker from Uzbekistan with a legal residence permit in Norway, and a 37-year-old Iraqi Kurd who also holds a Norwegian residence permit.

The latter suspect was arrested on Thursday in Germany, were he had spent several days as a tourist. Prosecutors in Frankfurt told AFP he would be extradited to Norway, but Norwegian media said he remains in German custody.

The two other men were arrested in Oslo, also on Thursday. They appeared in court on Monday where police asked for them to remain four weeks in custody, with bans on communications and visits.

Isolation of the suspects would be necessary to the investigation, Aalling told NTB, adding: "There is a great danger of tampering with evidence."

The lawyer for the Uzbek suspect told public broadcaster NRK on a break from the court hearing that his client had worked as an informant for the Norwegian security police (PST) since November 2009.