Lashkar-e-Tayiba operative David Headley's cell-phone and his Chicago apartment were registered in the names of dead persons and investigations have found that he was leading a double life under directions from the Pakistan-based terror outfit, according to the Federal Bureau of Investigation.
Meanwhile, a team of officials from the FBI and the Justice Department headed to Pakistan from Delhi today to follow up on leads after briefing Indian authorities on its investigations into the conspiracy involving Headley, a Pakistani-American, and his Pakistani-Canadian accomplice Tahawwur Rana, in the Mumbai terror attacks.
"We have been having close consultations with Pakistani authorities in this investigation and the joint FBI-Department of Justice Team will meet officials of various government agencies," said United States Embassy spokesman in Islamabad Rick Snelsire.
In New Delhi, Home Secretary G K Pillai said the terrorists were working on new strategies and the time has come to 'think the unthinkable'.
"As we have seen from the Headley case, one can still slip through the radar. Because nobody will look for a US citizen with an American passport and a business visa".
Headley, 49, has been charged by the FBI for helping plot last year's 26/11 attacks that left 166, including six American citizens dead and 304 injured. In August this year, deceptive answers at the airport about his travels abroad aroused the suspicion of officials and subsequently led to his arrest.
He was questioned by an inspector and ambiguous responses began to unravel his double life, the Wall Street Journal reported, quoting Law Enforcement officials.
On being quizzed, Headley said he worked with a company named First World Immigration Service which, investigators believe, provided him a cover to scout for terror targets for the LeT.
Headley's luggage was searched and it "contained no papers or other documents relating to such a business," according to court documents.