A report in Times Online quotes MK Narayanan as saying that the computers in his office and other government departments were targeted on Dec 15.
The hackers reportedly launched an attack using a 'Trojan' virus in order to access the computer remotely and download of delete files.
The virus was detected and officials were told not to log on until it was eliminated, the NSA told Times Online in an interview.
“People seem to be fairly sure it was the Chinese. It is difficult to find the exact source but this is the main suspicion. It seems well founded," he said.
The attack, which took place on Dec 15, happened to fall on the same day as US companies reported cyber attacks from China.
While China maintains that it had nothing to do with the hacking attacks, these cyber strikes are bound to further strain the Indo-Sino ties.
Last week, a leading Indian TV news channel Headlines Today reported hackers from China have targeted computers in the Prime Minister's Office (PMO) along with the cream of India's national security set-up including MK Narayanan among others.