By Indian accounts Markaz-e-Taiba is the dragon's lair — the headquarters of the Pakistani militant group that slaughtered 171 people in Mumbai last week.

The reality, when The Times visited yesterday, appeared rather more civilised. A lunch of spiced chicken, rice and bread was laid out across ten round tables in an immaculate rose garden inside the complex, 30 miles from the Pakistani city of Lahore.

Polite young men with long beards handed around bottles of mineral water as a spokesman held forth in impeccable English. The gunmen who normally patrol the 75-acre grounds were nowhere to be seen. “Welcome,” said a smiling guard as he frisked a visitor at the gate.

This was the friendly face of the Islamist movement now at the centre of the investigation into the Mumbai attacks — and a tense diplomatic stand-off between India and Pakistan.

Markaz-e-Taiba is the headquarters of Jamaat-ud-Dawa (JuD), an Islamist charity that says it does only peaceful social work. Indian officials insist that it is a front for Lashkar-e-Taiba (LeT), the Pakistani militant group that they and their US counterparts blame for the attacks in Mumbai, formerly Bombay.

So JuD, anxious to profess its innocence, invited reporters on a rare tour of its facilities near the town of Muridke in the central province of Punjab.

“All the allegations against us are baseless,” Abdullah Muntazir, a spokesman for the group who used to speak for LeT, told his visitors. “You can see what we do here.”

India says that the case against JuD is clear cut: its leader is Hafiz Saeed, the founder of LeT and one of the 20 people whose extradition was demanded from Pakistan by Delhi this week.

He left LeT shortly before it was banned for an attack on India's parliament in 2001, which almost caused a fourth war between the nuclear-armed neighbours.

The US is also pressing the Pakistani Government to act against JuD and other groups, to prove its commitment to co-operate with India's investigation. The White House urged it to “act with resolve” following talks between Asif Ali Zardari, Pakistan's President, and Condoleezza Rice, the US Secretary of State.

Some Indian hawks have even called for a military strike on Markaz-e-Taiba, which Mr Saeed founded in 1994 as a teaching centre for the Wahabi branch of Islam.

But the tour illustrates how difficult that could be for a weak civilian Government in a country of 165 million people, growing numbers of whom support JuD.

First, the group condemns the Mumbai attacks and denies any involvement. “What happened in Mumbai is not jihad,” said Mr Muntazir. “I don't see how any Muslim can carry out such a kind of thing.”

Secondly, it says that it does nothing illegal: its professed aim is to provide academic and religious education to Pakistani boys and girls neglected by the State.

Its complex includes two schools where 513 boys and 487 girls are taught the national curriculum, according to Rashid Minhas, the school principal.

“It is imperative that Muslims should learn science,” he said. The complex also contains a mosque, an Islamic seminary, a hospital, a carpenter's workshop, a guesthouse and several residential blocks.

The group's other stated goal is to provide relief from disasters, such as the 2005 Kashmir earthquake, after which its activists, many of them armed, were at the forefront of aid efforts.

Behind this respectable veneer, however, security officials and experts say that the group continues to recruit for LeT's campaign in Kashmir. Some suggest that it does so with the complicity of Pakistan's Inter-Services Intelligence agency, which founded LeT as a deniable proxy to fight India in Kashmir.

Posters and graffiti on the road from Lahore to Muridke exhort Muslims to join jihad, or holy war. Walls of the complex bear slogans such as “India is an occupier” and “Lashkar is coming”.

The group also publishes several magazines and runs a website containing reports of “Indian atrocities”.

Mr Muntazir said that the Mumbai attacks might have been carried out by “those victimised by Hindus”. “They are killing Muslims, Christians and other religious minorities,” he said. “It could be the reaction to that.”

Analysts say that the group has avoided trouble with Pakistani authorities so far because it has not become involved in attacks on targets inside Pakistan.

The US added JuD to its list of foreign terrorist organisations in 2006 and froze Mr Saeed's assets this year, but Pakistan has only put it on a watch list and Mr Saeed still regularly addresses large crowds in public.

Last month the group held a series of jihad rallies across Pakistan, which attracted hundreds of thousands of people. Mr Muntazir urged the Pakistani Government not to bow to pressure from India and the US — despite the threat of another military confrontation.

“We speak loudly. We let the general public know that India is the enemy,” he said. “They are making propaganda and trying to make the Government shut this place ... but we will never abandon it.”

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