“Kasab was convicted not on the basis of his confession but on the basis of the evidence gathered against him,” he said while replying to a discussion in the Rajya Sabha on the functioning of the home ministry.

“This was not only oral evidence but a wealth of material that was painstakingly gathered. We were able to reconstruct the path (of the 10 attackers) from Karachi to Mumbai. We were able to track mobile phone conversations within hours of the attack,” the home minister said.

He noted that through the use of technology, investigators “were able to retrieve material from damaged mobile phones. In a way, this was phone tapping”, he said in a reference to the controversy that rocked parliament on the phones of prominent politicians being tapped.Speaking about the course of the trial, he said: “We did not create a Guantanamo Bay. We did not create a military court. Kasab was tried in a normal civil court, except that the judge was designated a special judge.”

Kasab was Thursday sentenced to death for his role in the November 2008 Mumbai carnage by a special court that said he had no right to live.Special Judge M.L. Tahaliyani gave him death on four counts -- waging war against India, murder, conspiracy to commit murder and indulging in terrorist activities. "To be hanged by the neck till death," the judge intoned after reading out each count.