The Islamic fundamentalists who run the Markaz-e-Taiba complex near Lahore like to boast that it was inspired by Aitchison College, Pakistan's poshest private school. It is, as they describe it, the Eton of Wahhabi Islam, complete with polo ponies and a swimming pool.

Yet when it comes to their links to Pakistan's intelligence service and Lashkar-e-Taiba (LeT), the militant group blamed for last month's attacks in Mumbai, they seem to suffer from collective amnesia. “We've never had any connection to either,” Mohammed Abbas, the administrator of the complex, told The Times.

But it was here, in April 2001, that Hafiz Mohammed Saeed, LeT's leader at the time, called a meeting of his supporters in the 75-acre complex of red-brick buildings and neat lawns. Most of the visitors wore the obligatory long beards, but among them was an elderly man with no beard, only a thin, military-style moustache.

He was Hamid Gul, the former head of Pakistan's Inter-Services Intelligence (ISI) agency. “Yes, I visited there,” General Gul told The Times. “Retired army officers used to go, too. They used to hold annual fixtures to raise funds and motivate people.”

General Gul, 72, was the ISI chief from 1987-89 and had long since retired by 2001. Since the attacks in Mumbai, however, such meetings have added weight to India's assertion that Pakistani intelligence has close ties to LeT and other militant groups involved in attacks on Indian soil.

Pakistan's Government is under unprecedented international pressure to sever any such links and “rein in” an intelligence agency that is widely regarded as a law unto itself. Indian officials say that the ISI was complicit in Mumbai, and that the one captured militant has confessed to receiving training from a former ISI officer.

Washington wants four former ISI officers, including General Gul, to be added to the UN terrorist list. Senator John Kerry, the new head of the Senate Foreign Relations Committee, also made a direct appeal to President Zardari on a visit to the region last week. “It is imperative that the intelligence service of Pakistan [is not able] to make its own choices or operate outside of the standards that we have a right to expect,” Mr Kerry said.

The question is whether Mr Zardari is strong enough to comply: the ISI vetoed his efforts to place it under the Interior Ministry and to send its chief to India after the Mumbai attacks. Many Pakistanis also feel that the Government cannot comply without undermining their strategic interests in Kashmir and Afghanistan.

The ISI makes no secret of its former support for LeT and other militants as proxies to fight Indian rule in Kashmir and to offset India's influence in Afghanistan. “These jihadis were there and we supported them. I think any intelligence agency worth its name would have done the same,” one senior ISI officer told The Times.

His next remark summed up much of today's relationship between the ISI and the likes of LeT: “It's a monster we created and now we can't get it back in the bottle.”

The ISI had forged ties with jihadist groups throughout the 1980s when the CIA used it to support the Mujahidin against the Soviet Army in Afghanistan. When an uprising began in Indian-ruled Kashmir in 1989, the ISI saw an opportunity to weaken its neighbour. General Asad Durrani, ISI chief from 1990-92, denied supporting LeT in his tenure, but admitted that Pakistan had an interest in supporting such groups. “Given Kashmir's history, we can't be expected to remain uninterested,” he said.

The ISI officially severed links with LeT in 2002 after the group attacked India's Parliament, but Indian and US intelligence believe that it maintained covert support, probably through ex-ISI officers. Generals Gul and Durrani and the serving officer all admitted that some retired ISI agents may have shared the ideology of the militants.

All three said that it would be impossible to channel serious support to militants from inside or outside the ISI without the knowledge of the agency's leadership. As for the Mumbai attacks, they said that it was not in the ISI's interests to antagonise Washington and provoke another conflict with India during an economic crisis.

Many Indian and Western analysts agree, saying that the ISI probably trained LeT militants but was not directly involved in Mumbai. “There almost certainly are still ISI links to LeT, but the question is how much operational control does the ISI have?” Lisa Curtis, a former CIA analyst and South Asia expert at the Heritage Foundation, said.

She and other experts are urging Mr Zardari to appoint a civilian head of the ISI and dismantle all the militant groups it has supported. The ISI is unlikely to accept either solution until the international community also addresses Pakistan's concerns in Kashmir and Afghanistan. “Cleansing the ISI is America's dream, but this is Pakistan's first line of defence,” said General Gul. “It keeps the country united.”

Controversial ISI leaders

Hamid Gul 1987-89: admits ties to LeT leadership; banned from travel to Britain

Asad Durrani 1990-92: admits support for militant groups; fierce critic of US

Javed Nasir 1992-93: now belongs to an Islamic missionary movement

Nasim Rana 1995-98: began arming and training the Taleban in Afghanistan

Ziauddin Butt 1998-99: maintained close relationship with the Taleban government

Mahmood Ahmed 1999-2001: dismissed under pressure from the US after the September 11 attacks because of his Taleban links

Ashfaq Parvez Kayani 2004-07: favoured by the US, went on to become current Army chief

Ahmad Shuja Pasha 2008: formerly oversaw operations against militants in northern Pakistan

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