The former head of Pakistan’s ISI, Hamid Gul, tells Channel 4 News that he is “100 per cent sure” a Taliban attack on a major naval air base in Karachi was an “American operation”.

The Pakistani Taliban have claimed responsibility for a major assault on the headquarters of the naval air force in Karachi that killed at least thirteen officials and injured 14 others.

Eleven navy officers and two paramilitary rangers died in the attack at the PNS Mehran base in Karachi after 16 hours of intense fighting, involving 130 Pakistani commandos.

Interior Minister Rehman Malik said just six militants were believed to be involved in the attack, destroying or damaging two aircraft and laying siege to a main building in one of the most heavily-guarded bases in the unstable, nuclear-armed country.

There is absolutely no doubt that this was a US operation. Gen Hamid Gul, Former ISI Director

Eight major blasts were reported throughout the night as fighting intensified.

The Pakistani Taliban said the attack was to avenge al-Qaeda leader Osama bin Laden’s killing on 23 May.

“It was the revenge of martyrdom of Osama bin Laden. It was the proof that we are still united and powerful,” Taliban spokesman Ehsanullah Ehsan told reporters by telephone from an undisclosed location.

But General Hamid Gul, a retired three-star general who headed the Inter-Services Intelligence agency (ISI) from 1987-1989 and has been criticised by the US for his links with the Taliban, told Channel 4 News “there is absolutely no doubt that this was a US operation.”

He insisted: “The Karachi incident was clearly an operation by special forces, it must have taken months to plan, and the level of intelligence gathered is far too sophisticated for it to have been a raid by al-Qaeda or the Taliban,” he said.

“The reconnaissance and the surveillance to target three or four planes is far too advanced.”

Gul, who served as director general of the ISI when President Zardari’s late wife Benazir Bhutto was Prime Minister, said instability in Pakistan is: “the price for American friendship.

“There have been betrayals by Americans in the past, and there will be betrayals by Americans in the future. Absolutely they want to destabilise Pakistan because they want joint custody of nukes, to consolidate their position in the region, so a Karachi naval blockade is a natural move.”

The US State Department was contacted by Channel 4 News for a comment, but has not yet responded to the request.

Prime Minister Yusuf Raza Gilani responded to reporters by condemning the attack.

“Such a cowardly act of terror could not deter the commitment of the government and people of Pakistan to fight terrorism,” Gilani said in statement.

Operation details

Interior Minister Malik said the six militants aged 20-25 used two ladders to scale the 5ft walls of the base and jumped in by cutting barbed wire.

He said the militants had used guns and grenades in their attack on the base, which is 15 miles (24 km) from the Masroor Air Base, Pakistan’s largest and a possible depot for nuclear weapons.

Malik said 17 foreigners – including 11 Chinese and six Americans – were inside the base at the time. All had been evacuated safely.

Mullah Omar

In a separate incident, the Taliban in Afghanistan have rejected unsourced media reports that its reclusive leader Mullah Mohammad Omar has been killed in Pakistan, saying that he is alive and in Afghanistan.

Pakistan security officials, US military commanders and government officials in Afghanistan have offered tentative rejection of reports that Omar had been killed while travelling between Quetta and North Waziristan in Pakistan.

“He is in Afghanistan safe and sound,” Taliban spokesman Zabihullah Mujahid told Reuters by telephone from an undisclosed location. “We strongly reject these baseless allegations that Mullah Mohammad Omar has been killed.”

“This is the propaganda by the enemy to weaken the morale of fighters,” Mujahid said.

In Kabul, senior diplomats and US military officials also could not confirm the report and would not comment publicly. Some described the reports as “speculation.”