Headley, arrested earlier this month, had made several trips to India and intended to stay in the country for some time -- two to four weeks -- to execute the LeT plans, according to the US investigators.
49-year-old Headley was arrested along with a Canadian citizen of Pakistani origin by FBI's joint terrorism task force at Chicago's O'Hare International Airport before boarding a flight to Philadelphia, intending to travel to Pakistan.
According to an affidavit filed by the FBI in a Chicago court, Headley in an e-mail on July 8 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 was to 'Rahul,' a prominent Indian actor with that first name, the FBI said in its complaint.
Intelligence sources in New Delhi discounted speculation that the reference could have been to Congress leader Rahul Gandhi. In such cases, US security agencies immediately alert their Indian counterparts and there had been no such alert, the sources said.
The sources said that in the past US counter-terrorism agencies had tipped off India about the terror plots against VVIPs. The sources wondered whether 'Rahul' was codename for some other VIP target.
They are awaiting details of the FBI case in Chicago court. US ambassador to India Timothy Roemer refused to divulge details of the case saying, "We cannot comment on the ongoing investigations and judicial proceedings."
He described the arrest of the two persons by FBI as an 'important breakthrough.'
Responding to Headley's July 8 e-mail, the Lashkar leader said, "To see Rahul is a good idea coz (because) have some work for you over there too. Matters are good enough to move forward."
Not satisfied with the response, Headley wrote back on July 9, "When you say 'move forward' do you mean in the north direction or towards Rahul ?"
The leader clarified that move forward meant 'towards Rahul.' Headley wrote another mail to the leader on July 10 seeking clarifications on 'status of the northern project' and whether the visit to 'Rahul's place' was for checking out 'real estate property like before or something different.'
Other questions asked by Headley included, 'How long do you think I will need to stay at Rahul's place to complete this task' and 'will I have to stay there continuously for a while, or back and forth, like before.'