Pakistan's intelligence agency on Tuesday said it was embarrassed to have failed to capture Osama bin Laden but defended its record against mounting criticism of complicity.
That the al Qaeda chief lived a mile from Pakistan's equivalent of West Point, where the head of the army a week earlier claimed Pakistan had broken the back of militancy, has fuelled suspicions that it has played a double game.
For years, Pakistan said bin Laden was dead or abroad, but it took a US squad just 40 minutes to raid his house and fly off with the body, a mere 30 miles (50 kilometres) from the capital.
Intelligence officials said Pakistani agents raided the compound in 2003 while it was still under construction, looking for then al Qaeda number three Abu Faraj al-Libbi, who escaped and was eventually captured two years later.
They said the Inter-Services Intelligence (ISI) agency had no idea bin Laden had been holed-up in the sprawling compound in the town of Abbottabad.
One official said it was embarrassing, but insisted that the ISI's record in capturing and killing hundreds of other militants should not be forgotten.
"It (the compound) slipped from our radar," he told AFP, referring to the period after the 2003 raid to capture Libbi, who escaped until Pakistani agents arrested him in 2005 in the northwestern district of Mardan.
During their interrogation of Libbi, CIA agents reportedly became convinced that he had been in contact with the same courier, who eventually led them to bin Laden.
"It was an embarrassment to an extent that yes we failed to locate him, but the fact of the matter is, in the last 10 years the contributions that we made are suddenly being overlooked," the ISI official told AFP.
"The number of people of al Qaeda we have captured and killed runs to hundreds. The number of people that we have picked up from the Taliban also runs to the hundreds, so one failure makes us out to be incomptent?"
"Had we known he was there, we would have captured him and handed him over to the Americans to silence the critics," the official said.
Civilian leaders, whose relationship with the military is far from close, have called for an investigation into the failure.
"We will inquire into the causes of what happened but it's really important not to turn it into any allegation of complicity," Pakistan's ambassador in Washington, Husain Haqqani, told AFP.
The ISI, formed in 1948 shortly after independence from British rule, plays a key role in Pakistan, which has spent more than half its 64-year existence under military rule.
It funneled weapons bought with US cash to Muslim fighters battling the Soviet occupation of Afghanistan in the 1980s, a war that spawned al Qaeda.
The organisation has been credited with creating the Taliban, the Islamist militia that fought its way to power in Kabul in 1996 and ruled until the 2001 US-led invasion after the 9/11 al Qaeda attacks in the United States.
The agency has arrested numerous al Qaeda leaders. The most high profile was the 2003 arrest of Khalid Sheikh Mohammed, the self-confessed mastermind of 9/11, in the garrison city of Rawalpindi.
But the West has long harboured suspicions that Pakistan, and particularly elements within the ISI, failed to cut all ties with militants.
Ten days before the bin Laden operation, the top US military officer Mike Mullen accused the ISI of having a long-standing relationship with the al Qaeda-affiliated Haqqani network.
Western analysts suspect the ISI is divided, with elements increasingly seeing militants as a domestic threat after Taliban and al Qaeda-linked bombings killed more than 4,240 people in Pakistan in the past four years.
Pakistan has traditionally seen India as the enemy, nurturing Islamist groups to fight in India-administered Kashmir and fostering the Taliban in Afghanistan to offset the growing might of its eastern neighbour.
But while both sides have attested to cooperation between the ISI and the CIA, bin Laden was killed when ties were at an all-time low.
Earlier this year Pakistan and the United States were at loggerheads over Pakistan's detention of a CIA contractor, Raymond Davis, who was arrested after killing two men in broad daylight and accused by police of double murder.
After his release, the ISI reportedly demanded that the CIA cut back legions of operatives and special forces from its territory.
Given the trust deficit, Pakistani security analyst Imtiaz Gul said it was unsurprising the US failed to inform the ISI of the raid.
"At least some people within the security apparatus would have probably known," he said.
"A lot of people within the bureaucracy, within the military establishment, the society, came to support and adore Osama bin Laden and his mission against the United States," he said.