"The FBI team is visiting India on Dec 7 and 8. We hope they have lots of key information about the two terror suspects," the official said without divulging any detail.
"Nobody knows it. We are waiting for them. Let's see what they have to share with us," said the official requesting anonymity.
The decision of the Federal Bureau of Investigation (FBI) to come to India follows intensive discussions between Prime Minister Manmohan Singh and US President Barack Obama in Washington last month.
On Oct 3, the FBI had arrested Headley, a Pakistani born national but settled in the US, for alleged links with an international terror network.
Rana, a Canadian citizen and Headley's accomplice, was arrested on Oct 18. Rana was living legally in Chicago, where he operated an immigration centre.
According to investigators, Headley and Rana were working on behalf of the Pakistan-based Lashkar-e-Toiba terror outfit and were planning new terror attacks in India.