On May 21, 2009, Ajmal Amir Kasab, the sole surviving Pakistani gunman from the 26/11 attack, was giving evidence in the court of Justice M.L. Tahaliyani at Mumbai's Arthur Road prison. Suddenly, he dropped a name. The person, he said, who had been their principal guide during the 60-hour operation from a control room in Karachi was Abu Jundal. No one in India had heard this name. Some were puzzled. Prosecution lawyer Ujjwal Nikam believed it was misinformation. And, as so often, the name Abu Jundal disappeared into a file.

Three years later, on June 21, 2012, Saudi Arabia bundled a wanted Lashkar-e-Toiba (LeT) operative, Syed Zabiuddin Ansari, 30, on a plane and sent him to New Delhi. Ansari had more than one alias; among them was Abu Jundal. When Kasab, from his Mumbai cell, heard that Abu Jundal had been deported by the Saudis and was a captive in India, he became, say his jailors, contemplative. The final pieces of a complex puzzle was coming together. Perhaps the most deceptive element in the exhaustive planning that had gone into the barbaric terrorist attack on Mumbai, conceived by the Inter-Services Intelligence (ISI) and implemented by LeT, was a poisonous sting in the tail. When the horror that took 166 lives was over, the ISI wanted to leave behind enough false trails to implicate Indians for its most spectacular offensive against India.

DEADLY DECEPTIONS ISI wanted to leave enough red herrings to implicate Indians in the 26/11 attack Fake identities: The attackers carried ID cards of Arunodaya College, Hyderabad. The college is genuine but the ID cards were fake. Threads of distractions: LeT plotter David Headley purchased wristbands for all 10 attackers at Mumbai's Siddhivinayak temple. Blame it on Indians: 'Kharak Singh from India' bought the Internet calling service used by LeT handlers. His IP address was in Pakistan. Lies on live television: "We're from Hyderabad. Don't you know Hyderabad? Don't you know your country?" attacker Fahadullah told a TV channel. Numbers game: All 10 terrorists were given mobile phones with Indian SIM cards by LeT's communications chief Zarar Shah.

It was a plot in which Ansari was a key protagonist. Born in Gevrai village in Maharashtra's Beed district, he completed his matriculation and did an Industrial Training Institute course to become an electrician. He became an anti-India radical after the 2002 Gujarat riots and went into the shadows of terrorism, first joining the Students Islamic Movement of India (SIMI), then the LeT.

Ansari came on the police radar for another plot against India, in transporting a shipment of 43 kg of RDX, 16 AK-47 assault rifles and 50 hand grenades to Aurangabad in 2006. This shipment, meant for a terror attack, was intercepted by the Maharashtra police. Under pressure, Ansari contacted LeT and fled to Pakistan. His name entered the public domain when the Indian Government handed over a list of 50 Most Wanted Fugitives to the Pakistani authorities in March 2007.

But Ansari was proving to be an invaluable asset for the LeT. A highly committed operative, he knew the layout of the land and directed terrorists during the attack on Mumbai on November 26, 2008. He was involved in plotting the blast at Pune's German Bakery on February 13, 2010, that killed 17 people. But still, India did not know of his role in the 26/11 attack. The breakthrough came in May 2010 when the Delhi Police intercepted a call from an India-based terrorist, Ajmal, who was in touch with his Pakistani handler. Ajmal had planned an attack on foreigners during the Commonwealth Games in Delhi that year. He referred to his handler as Abu Jundal. The agencies tracked Jundal down inside Pakistan. He was using the alias of Riyasat Ali and shuttled between LeT's headquarters in Muridke, near Lahore, and Karachi. Then they made a stunning discovery. Jundal, Riyasat Ali and Zabiuddin Ansari were the same person. Now they waited for their target to travel out of Pakistan.

In early 2011, Pakistan issued a passport to him, and sent him to Saudi Arabia to recruit potential jihadis from Indian labourers on behalf of LeT. In the oil-rich port of Dammam, Ansari ran a small taxi rental business, posing as Pakistani national Riyasat Ali. The US intelligence alerted the Saudis about Ansari's terrorist links; Riyadh put him under surveillance. Meanwhile, New Delhi provided the Arab kingdom with proof that Riyasat Ali was Zabiuddin Ansari, an LeT operative and originally an Indian citizen. DNA samples of his relatives were sent to the Saudi government even as the home ministry provided evidence of Ansari's involvement in the Aurangabad arms haul case. Islamabad, fearing that his deportation could explode their ploy of deniability, still maintained that he was a Pakistani citizen and wanted him back.

But the Saudis interrogated Ansari and discovered that he was indeed an LeT operative. They had to take a call. Should they stand by their long-time ally Pakistan and let Ansari remain in Dammam or stand by international law and hand him over to India? The Kingdom chose India.

At a safe house of the Delhi Police's Special Cell in the Capital's Lodhi colony, Ansari has been telling his interrogators details of the secret plot at the core of the deadly attack on Mumbai. The intent was to land a double sucker punch. The first blow would devastate Mumbai. The second blow would, with just enough 'evidence', promote conspiracy theories among a section of media, opinion makers and political leaders that Hindu militants were behind the carnage.

Hemant Karkare during the 26/11 attack. Hemant Karkare during the 26/11 attack.

The conspiracy theorists didn't let Pakistan down. "There is more to it than meets the eye," former Maharashtra chief minister Abdul Rehman Antulay said outside the Lok Sabha on December 18, 2008, about the death of Maharashtra Anti-Terrorism Squad chief Hemant Karkare. Karkare, Additional Commissioner Ashok Kamte and Inspector Vijay Salaskar had been ambushed and killed by Ajmal Kasab and his accomplice Ismail Khan on November 26, 2008. Karkare was probing the Malegaon blasts, which had resulted in the arrests of Hindu fringe elements such as Lt-Col Shrikant Prasad Purohit, Sadhvi Pragya Thakur and Swami Aseemanand. Much of the Urdu press in India placed the blame for the attack on a diabolical Zionist-RSS nexus. Aziz Burney, group editor of leading Urdu newspaperblamed Hindu extremists. 'Is there any connection between the 26/11 attack and the Malegaon terror attack?' screamed a headline in the daily on November 29. 'This is a joint terror operation by Sangh Parivar and Mossad' said theof November 30, 2008. On December 5,ran another story: 'Who do you believe, Kasab the terrorist, or Karkare the martyr?' The paper hinted that the 26/11 attack was the work of Hindu fundamentalists and an elaborate plot to silence Karkare. 'Hindu terrorists are behind Mumbai attacks' said the Akhbare Mashriq on December 6, 2008. In September 2009, a retired Maharashtra inspector-general of police, S.M. Mushrif, in his book, blamed the Intelligence Bureau and Hindu extremists for 26/11.

The conspiracy theory was also enthusiastically bought by politicians who wanted to mine the Muslim vote. On December 6, 2010, senior Congress leader and former Madhya Pradesh chief minister Digvijaya Singh released Burney's book, which accused the RSS of planning and executing the 26/11 attack. Five days later, Singh claimed that Karkare had rung him up hours before he was gunned down and complained about threats and pressure from radical Hindu groups.

Ansari's confessions have further unravelled the secret Pakistani plot. He told interrogators of his role in teaching the 26/11 attackers Hindi. He would give them Hindi magazines and conduct conversations with them to sharpen their language skills before they left Karachi. He taught the attackers to blend into India-greet people with a proper 'namaste', maintain a low profile and be polite to women. There were other aspects to this smokescreen-the terrorists were made to wear sacred red threads bought for Rs 20 each by LeT scout David Coleman Headley from Mumbai's Siddhivinayak temple. All 10 terrorists carried fake identity cards of Arunodaya College, located in Hyderabad. They also took Hindu names. Ajmal Kasab became Sameer Choudhary and Ismail Khan was Naraish Verma. An LeT operative pretended to be 'Kharak Singh from India' and purchased Internet calling services from a US-based firm for $250 (Rs 10,000). The terrorists were told to communicate with their Karachi-based handlers using phones with Indian SIM cards.

The LeT, according to Ansari, monitored the attack from a specially created military-style command and control centre in Karachi, which was visited by LeT leaders and ISI officials. The control room had multiple television sets tuned into Indian TV channels, satellite telephones and computers. The handlers-Sajid Mir, Abu Al Qama, Abu Qahafa and Muzzammil-maintained constant communication with the 10 terrorists. Ansari tutored two of the LeT terrorists who had stormed into Nariman House on what to tell the Indian media in Hindi. He asked them to impersonate disgruntled Muslim youth. While doing this, he used a Hindi word prashaasan (administration). Indian intelligence agencies who tapped into the conversation were intrigued by the use of a Hindi word by a Pakistani controller.

Actually, Pakistan's web of deceit had begun imploding with the arrest of Headley, the LeT scout, by the US Federal Bureau of Investigation in June 2010. He told his Indian interrogators that the Pakistan Army and ISI were deeply involved in the 26/11 attack. He was in touch with two serving ISI officers, Major Iqbal and Major Samir Ali. Headley also made the chilling revelation that every senior LeT leader was "handled" by an ISI operative.

Ansari's interrogation brings fresh embarrassment for Pakistan. He has revealed the presence of Pakistan's ISI in the control room that the let set up to monitor and direct the attack. Ansari also clarified that the LeT has been unaffected by the arrest and ongoing trial of masterminds Zakiur Rehman Lakhvi and Zarar Shah at an anti-terrorist court in Rawalpindi's Adiala Jail. The organisation is still plotting fresh attacks against India. The LeT is widely believed to be a proxy arm of the Pakistan Army. Its battle against India spilled out from Jammu and Kashmir to the Indian mainland. It was designated a "Foreign Terrorist Organisation" by the US in 2001 but the Americans saw it as an international threat only after the 26/11 attack. In April this year, US Secretary of State Hillary Clinton announced a $10 million (Rs 50 crore) bounty for information leading to the arrest and capture of LeT supremo Hafiz Saeed.

What rankles Pakistan is that Ansari was arrested and deported by its closest ally, Saudi Arabia. The kingdom wields almost undiminished power over Pakistan's army and political establishment. Through the deportation of Ansari, it has indicated that it will no longer provide protection for Pakistan's terrorists. Another suspected terrorist, Fasih Mehmood of the Indian Mujahideen, has been detained by Saudi Arabia for his role in the twin blasts outside Bangalore's Chinnaswamy stadium on April 17, 2010. He faces imminent deportation to India.

Now that the conspiracy has been exposed, some of its original theorists have backtracked. Digvijaya Singh says he had already clarified about his post-26/11 comments. "There is nothing more to say. I am happy that Home Minister P. Chidambaram has upped the ante on the terror issue and has pressed Pakistan to admit facts relating to Jundal having trained terrorists who attacked Mumbai," he told India Today. Antulay called his November 27 statement "a genuine mistake". "Multiple theories were floating in the aftermath of the attack, especially the one revolving around the death of Karkare," he said.

Antulay admitted, however, that the Hindu terror angle had momentarily deflected the nation's attention from the LeT. Mushrif now refuses to comment because the 26/11 case is subjudice but says he never questioned Pakistan's role in the attack. "If someone wants to comment on this issue he should approach the court and seek a reinvestigation," he said. Burney's newspaper ran a front-page apology on January 29, 2010. Burney himself is, however, unapologetic and says many questions on 26/11 remain unanswered. Film producer-director Mahesh Bhatt says there is no denying Pakistan's involvement but refuses to believe the theories being floated by Indian investigators now and calls for a debate. "After the 9/11 attack, people in the US raised questions on the identity of the attackers. Nobody was apologetic about their views," he says.

Kavita Karkare, the widow of Hemant, believes recent developments have vindicated her stand that the attack was not an inside job. "I have been saying since the beginning that no Hindus are involved in it. Many people floated stories for political reasons. They fell flat," she says.

Pakistan's Interior Minister Rehman Malik. Pakistan's Interior Minister Rehman Malik.

Pakistan, though, remains unapologetic even as it tries to distance itself from its Indian collaborator. On June 27, just a week after Ansari's arrival in India, Pakistan's Interior Minister Rehman Malik hurriedly called for a press conference. "Now things are getting clarified," Malik said. "Who knows if there was a sting operation by somebody from India?" Malik, while defending his army and the ISI, was silent on how Ansari, an Indian citizen, managed to get a Pakistani passport and a National Identity Card for Overseas Pakistanis. In the run-up to the July 4-5 foreign secretary-level talks between India and Pakistan in New Delhi, an anonymous source in the Pakistan foreign office told the media that 40 Indians were involved in the Mumbai attack.

Clearly, one Ansari has not dampened the spirit of the world's most dangerous benefactor of jihad. Wait for the next round of conspiracy theories, written and sold by Islamabad.

- With Shantanu Guha Ray, Kiran Tare, Bhavna Vij-Aurora and Mohammad Waqas