Washington, Mar 09: The recent arrest in Pakistan of top al-Qaeda lieutenant Khalid Sheikh Mohammed was the result of months of tracking the terrorist's 10 cell phones by the US Echelon spy system, 'US News and World report' has reported. His March 1 capture by US and Pakistani police has yielded "some of the best intelligence in years" about the terrorist network, the news weekly said yesterday in an advance of its Monday edition. It quoted a high-level official as saying the US national security agency's Echelon surveillance system was used to monitor more than 10 cellphone numbers Mohammed used. "The Echelon system links phone numbers and voices and can locate these phones by triangulating with cellphone sites and satellites, said the weekly. "They were tracking him for some time," the official was quoted as saying. "He would shift, they would follow."

Computers, documents and cellphones seized during his arrest have revealed, among other things, that Iran is sheltering more than 100 of the network's operatives, the magazine reported.

"There are an increasing number of key al-Qaeda leaders hiding out in Iran, where local officials generally have been unwilling to hand over suspects to the United States and its allies," it said.

Mohammed, who was al-Qaeda's operations chief, was in direct and frequent contact with network leader Osama bin Laden, according to the magazine.

Bureau Report