Three suspected al-Qaida members were arrested Thursday morning in what Norwegian and U.S. officials said was a terrorist plot linked to similar plans in New York and England.
The three men, whose names were not released, had been under surveillance for more than a year. Officials believe they were planning attacks with portable but powerful bombs like the ones at the heart of last year's thwarted suicide attack in the New York City subway.
U.S. Attorney General Eric Holder has called that one of the most serious terrorist plots since 9/11. On Wednesday, prosecutors revealed the existence of a related plot in Manchester, England. Officials believe the Norway plan was organized by Salah al-Somali, al-Qaida's former chief of external operations, the man in charge of plotting attacks worldwide.
The officials spoke on condition of anonymity because they were not authorized to discuss the case. The Norwegian Police Security Service said only that the three were arrested on suspicion of "preparing terror activities."
Al-Somali, who was killed in a CIA drone airstrike last year, has been identified in U.S. court documents as one of the masterminds of the New York subway plot. Two men have pleaded guilty in that case, admitting they planned to detonate explosives during rush hour. A third man awaits trial.
A news conference was planned for later Thursday.
Officials said it was not clear the men had selected a target for the attacks but they were attempting to make peroxide bombs, the powerful homemade explosives that prosecutors say were attempted in both New York and England.
U.S. and Norwegian counterterrorism officials worked closely together to unravel the Norwegian plot, officials said. Janne Kristiansen, the head of the Police Security Service, traveled to the U.S. this spring to discuss some of the closely held intelligence that been gathered in the case.
In Washington, Justice Department spokesman Dean Boyd had no comment.
Officials did not say why Norway was a target, but al-Qaida No. 2 Ayman al-Zawahri has called for attacks on Norway, among other countries.
Magnus Norell, a terrorism expert at the Swedish Defense Research Agency, said Norway's 500 troops in Afghanistan could be a factor, as could the 2006 controversy sparked by a Danish newspaper's publication of 12 cartoons depicting the Prophet Muhammad.
Norell said the controversy has extended to neighboring Norway and Sweden after newspapers there republished the cartoons and later published similar cartoons. Images of Muhammad, even favorable ones, are considered blasphemous by many Muslims.
Apuzzo and Goldman reported from Washington.
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