Washington, Nov 7 (IANS) India has been kept informed about the case of two Pakistan-born Chicago men charged with planning a terrorist attack in India with the help of Pakistan based terror outfit Lashkar-e-Taiba (LeT), according to a US official.

"All I can really tell you from our diplomatic angle is that I know that our Ambassador (Timothy J. Roemer) has briefed the Government of India on the case, and we continue to follow the case," State Department spokesman Ian Kelly told reporters Friday.

But he declined to give details of the interrogation of the two suspects saying, "I'm not at liberty to divulge the details of the interrogation."

It's an ongoing legal case, and it is really in the purview of the Department of Justice, he said, "But I do know that we have briefed the Government of India on the broad parameters of the case."

Asked about a low-key visit of the Indian national security advisor, M K Narayanan ahead of Prime Minister Manmohan Singh's upcoming state visit, Kelly said he was not on a secret mission and had meetings among others with officials at the State Department.

"I don't think it was a secret mission," he said. "I just would - I would not encourage you to use the word 'secret mission.' I'm pretty sure he did have meetings here in this building."

Asked if Narayanan's visit had anything to do with the arrests in Chicago or a high alert in India ahead of the first anniversary of the 26/11 Mumbai terror attacks, Kelly said, "I don't know. We'll see if we can get you more information."

Prosecutors told a Chicago Federal court Tuesday that a Chicago businessman Tahawwura Hussain Rana had discussed an attack on India's National Defence College with David Coleman Headley, a Pakistan-born American national, in association with LeT.

Rana, a Pakistan-born Canadian national, and Headley, whose former name was Daood Gilani, are also charged with plotting to attack Danish newspaper Jyllands-Posten. The newspaper sparked outrage throughout the Muslim world in 2005 by publishing 12 cartoons depicting the Prophet Muhammad.

A team of officials from two Indian intelligence agencies, the Intelligence Bureau (IB) and the Research and Analysis Wing (RAW), arrived in the US Monday to join the US Federal Bureau of Investigation (FBI) in probing the foiled terror plot.

The officials were expected to interview at least Headley in a bid to determine the intended target in India and when the alleged attack was to be carried out.