Colonel Sadatullah is the highest-ranked Pakistani national to be implicated in the three-day siege which left 164 people dead

Indian police have named a Pakistani colonel who they say was connected to November's Mumbai terror attacks which left 164 people dead.

An 11,509-page charge sheet filed by the Mumbai police yesterday named the officer as Colonel Sadatullah, the highest-ranked Pakistani to be implicated in the three-day siege of two luxury hotels and other sites that strained tensions between the two neighbours.

Sadatullah is a colonel in the special communications organisation (SCO), a telecommunications agency of the Pakistani government run by officers from the army's signal corps. The SCO operates only in the Pakistani side of the divided province of Kashmir and Pakistan's restive northern region.

According to the Times of India, a total of 284 calls totalling 995 minutes were made to Pakistani handlers by the terrorists using mobile phones from the Taj Mahal hotel, Oberoi-Trident and Nariman House, a Jewish centre.

Indian investigators say the calls were made using voice over internet protocol, or VoIP, a cheap way of making international calls. They were traced to an IP address created with CallPhonex, a VoIP service provider based in New Jersey, in the US. Payments for the calls were made by opening an account in the name of Kharak Singh, from India.

However, payments to the account were made by wire transfer through MoneyGram and Western Union Money Transfer by two Pakistani nationals, Javed Iqbal and Mohammed Ishtiaq. The two used the email address ID kharak_telco@yahoo.com to communicate with CallPhonex. Indian investigators say there was contact between this email address and Sadatullah's official email, pmit@sco.gov.pk, which police say is the email service for all SCO officers.

Indian officials have charged a Pakistani national, Mohammed Ajmal Kasab, 21, who was captured in the early hours of the attacks. The sole surviving attacker faces 12 criminal charges, including murder and waging war against India. He could face the death penalty if convicted.

The other nine attackers were killed. India's special public prosecutor, Ujjwal Nikam, said he expected the trial to begin in the coming weeks and conclude within six months, but the legal process could drag on for decades. The trial for the country's deadliest terror attack, the 1993 Mumbai bombings which killed 257 people, lasted 14 years.

The Kasab trial could further inflame tensions with Pakistan as it sets out the role of Pakistani groups in the assault.

India blames the attack on Lashkar-e-Taiba, an Islamist militant group widely believed to have been created by Pakistani intelligence agencies in the 1980s to fight Indian rule in Kashmir. But the charges do not mention Pakistan's powerful intelligence agency.

India says all 10 attackers were from Pakistan. Pakistani officials have acknowledged that the attacks were partly plotted on Pakistani soil and announced criminal proceedings against eight suspects. The case against Kasab includes his confession, accounts from more than 2,000 witnesses and closed circuit television footage that shows him and an accomplice walking into Mumbai's crowded Chhatrapati Shivaji train station and opening fire.