According to the US Federal Bureau of Investigation (FBI), Headley and Tahawwur Hussain Rana, a Canadian citizen of Pakistani origin, were in touch with senior LeT operatives and other top terrorists in Pakistan, including Ilyas Kashmiri, a terrorist with links to Al-Qaeda and the Harkat-ul-Jihad Islami (HUJI), a Pakistan-based terrorist outfit.
“After establishing that Headley operated a visa agency in Mumbai for almost two years until July 2008, we are trying to find out if he was aware of the strikes and if he was involved or aware of the planning,” a top intelligence official told IANS.
“The investigation team which is in Chicago is armed with the details and their exact role will be known soon.”
According to intelligence sources, the firm called Immigrant Law Centre was run from AC Market, Tardeo in Mumbai that helped semi-skilled workers obtain visas for travel to the US and Canada.
Headley, a Pakistani national, acquired US citizenship after changing his name from Daood Gilani and travelled to India on business visas nine times between 2006 and 2009.
Mumbai's Joint Police Commissioner Rakesh Maria, who is leading the 26/11 investigation, has already stated that the police had all details of where Headley stayed in the city and for the periods as well.
The team is also trying to ascertain if Rana was in Mumbai days before the terror strikes.
The investigation team comprising officers of the Research & Analysis Wing, India's external intelligence agency, and the Intelligence Bureau are also keen to solve the 'Rahul' puzzle, a name that had cropped up during the FBI's interrogation.
A mysterious 'Rahul' appeared to have been the prime target of Headley and was part of the LeT's plans.
An affidavit filed by FBI in a Chicago court stated that Headley in an e-mail in July to a senior LeT leader whose name has not been revealed but who has been identified as 'LeT individual A', said: "I think when we get a chance we should revisit our last location again and say Hi to Rahul".
Following his arrest, Headley has stated that the reference Rahul was to a prominent Indian actor with that first name, the FBI said in its complaint.
Last week Home Minister P Chidambaram stated that 'Rahul' figuring as a target of Headley was not Congress general secretary Rahul Gandhi.
The bail application of Rana is scheduled to come up before the court this week and that of Headley in December.
Headley was arrested on Oct 18 along with Rana by the FBI at Chicago's O'Hare International Airport before boarding a flight to Philadelphia intending to travel to Pakistan.
Both were childhood friends and students of the same military school in Pakistan. The duo have been charged with aiding terrorists and could face up to life in prison if convicted.
They are also accused of conspiring with another man to plot an attack on a Danish newspaper that published cartoons of Prophet Mohammed in 2005.