THE 10 terrorist commandos who shot dead more than 160 people in Mumbai last month were among 500 trained to elite standards by Pakistan army and navy instructors, according to an Indian intelligence report seen by The Sunday Times.

Details were leaked as Indian officials accused Pakistan’s powerful Inter-Services Intelligence agency (ISI) of directly supporting the attack. They claimed to have the names of the gunmen’s ISI trainers and handlers and to have intercepted internet phone calls between them.

Last week Condoleezza Rice, the American secretary of state, and Admiral Michael Mullen, the chairman of the joint chiefs of staff, flew to Pakistan to intensify pressure on President Asif Ali Zardari and General Ashfaq Kayani, his army chief of staff, to appease Indian anger and stop tension between Delhi and Islamabad from escalating into war.

Mullen is understood to have told his Pakistani counterpart that America had proof that the attacks were launched from its soil by the Lashkar-e-Taiba (LeT) group, which has close links to the ISI.

America and Britain are keen the friction should not distract Pakistan’s forces from their offensive against Al-Qaeda and Taliban “safe havens” in tribal areas close to the Afghan border.

However, sources close to Indian intelligence claimed that another attack before next year’s general election would make war inevitable. Police in Calcutta were yesterday holding two men accused of illegally providing Sim cards for mobile phones used by the attackers. One was claimed to be a counter-insurgency police officer who may have been on a clandestine mission.

The Indian intelligence report claims the Mumbai gunmen were among a large group of volunteer “fedayeen” trained in commando tactics by Pakistan army and navy instructors over 18 months from December 2006.

“The training of these 500 men was in three phases. The first was basic physical fitness and firearms training. The second was marine navigation and swimming. The third involved training to sabotage underwater installations such as oil rigs, ships and submarines,” said one official.

“They were trained to a level of US Seals or Pakistani marine commandos. They were elite. Ten of these men were the ones who attacked Mumbai.”

If true, this training would have been in addition to later preparation said to have been given by LeT, the Al-Qaeda-linked group allegedly behind the attacks. The group was created with ISI support in the 1990s to fight in Afghanistan and Indian-administered Kashmir.

Investigators in Mumbai said the sole surviving gunman, Ajmal Aamer Kasav, had told interrogators he had been trained in marine commando skills by an LeT instructor named Abu Yusuf, also known as Muzamil, who is one of three Pakistan-based LeT leaders named by Indian officials as planning the attacks. The other two blamed by India are Hafiz Mohammad Saeed, who is believed to be the group’s leader, and Zaki-ur-Rahman Lakhvi, one of his long-standing senior commanders.

Saeed, who now heads the Jamat-ud-Dawa Islamic charity, which operates schools and hospitals in Pakistan, has denied involvement in the attacks, as has the LeT. The organisation was banned in Pakistan after the September 11 attacks on America but has grown and is now believed to have 20,000 supporters who have undergone military training. Last week Khalid Khawaja, a former senior ISI official, said that Saeed and Lakhvi were well known to his agency.

Khawaja was speaking after claims that the United States had asked the United Nations to add his name and those of two other former ISI officials, Hamid Gul and “Colonel Imam” (not his real name), to a blacklist of terrorists.

Senior US officials believe “rogue and retired” ISI officials have helped Taliban and Al-Qaeda terrorists carry out a number of attacks, including last July’s bombing of the Indian embassy in Kabul, which killed 58.

“It’s pretty clear that the LeT was behind the attacks. There is nothing that would point at the moment to direct links between the attacks and the ISI, but the ISI has a long association with the LeT and helped to create it,” said a western diplomat.

“The Indians don’t believe it is rogue and retired elements. In the Kabul embassy attack in July, the link [to the ISI] was more direct. But this is how they work, through retired officers.” Senior jihadi sources said there was jubilation within the LeT’s ranks.

Khawaja said that, while he did not approve of the Mumbai killings, “the Bombay attack should be seen as a good lesson to the world, to the Indians, the Americans, that if 10 committed people can do this, they’re igniting millions of youngsters, that they can do anything”.

Times Recommends

• 'New York has lost its edge'
• Copenhagen will fail – and quite right too
• More than 17,000 new underwater species found