WHEN an American warplane opened fire on a speeding car in the Jazira desert northwest of Baghdad earlier this month, the pilot had no way of knowing that among the insurgents fleeing a US military advance was Abu Musab al-Zarqawi, the most wanted terrorist in Iraq.

An air-to-ground missile struck close to one of three cars that had been spotted leaving the area near al-Qaim, where more than 1,000 US marines had launched Operation Matador, a sweep aimed at insurgent hideouts in small towns close to the Syrian border.

The other cars raced for cover as the warplane disappeared. When the smoke from the blast cleared, the insurgents found Zarqawi seriously wounded with a piece of shrapnel lodged in his chest.

Three weeks later a senior insurgent commander with close contacts to Zarqawi’s group, known as Al-Qaeda in Iraq, has provided a detailed account of Zarqawi’s brush with death.

The Jordanian-born terrorist is believed to be in Iran, where Al-Qaeda sympathisers may be helping him to move to a safe haven in an unnamed neighbouring country for surgery.

The commander revealed that Zarqawi had suffered two serious shrapnel wounds and light burns as a result of the missile attack. “Shrapnel went in between the right shoulder and his chest, ripped it open and is still stuck there,” he said.

The second piece of shrapnel penetrated the same area of Zarqawi’s chest but exited from his back. “There was concern about spinal injuries,” the commander added. “But his ability to move eliminated that fear.”

Zarqawi was carried to the other vehicles and taken to a hideout where he received basic first aid. He initially refused to be taken to hospital, but according to the commander his condition deteriorated.

When he became delirious with fever four days later, aides took him to the general hospital in Ramadi, 50 miles west of Baghdad. A local reporter confirmed to The Sunday Times two weeks ago that Zarqawi had appeared at the hospital, but had left as soon as his wounds were treated.

The man who allegedly masterminded a grisly succession of kidnappings, executions and suicide bombings in Iraq had been a prime coalition target since Arab television networks circulated gruesome videotapes of the beheading last year of Nicholas Berg, a young American entrepreneur who was seized by insurgents as he sought new business opportunities. Zarqawi is believed to have wielded the knife that killed Berg.

Previously regarded by intelligence agencies as a dangerous but comparatively low-ranking associate of Osama Bin Laden, Zarqawi was identified in 2003 by General Colin Powell, then the US secretary of state, as a supposed link between Al-Qaeda and Saddam Hussein. In Powell’s controversial presentation to the United Nations of evidence of Saddam’s terrorist connections, Zarqawi was said to have recuperated in Iraq from injuries that he reportedly received in Afghanistan.

Berg’s execution elevated Zarqawi to what one American magazine described as “terrorist superstardom”. As the insurgency grew more violent last year, he became a convenient scapegoat for US officials who were anxious to portray the rebellion as a foreign-led intervention in Iraqi affairs and not as a popular uprising.

The $25m (£13.8m) bounty on Zarqawi’s head eventually matched that of Bin Laden. Although US officials insisted that he was not the prime target of Operation Matador, intelligence sources confirmed that the coalition had received tips that he might be in the al-Qaim area.

Once Matador was launched there were reports of insurgents fleeing across the nearby Syrian border. But after his visit to Ramadi, Zarqawi is believed to have travelled east to Iran, where Al-Qaeda militants with connections to hardline Iranian revolutionary guards were waiting to help him.

A US State Department report noted recently that Al-Qaeda members had found a “virtual safe haven” in Iran, adding that the country’s long rugged borders were “difficult to monitor”.

Reports of Zarqawi’s fate are being examined in Washington, where a senior official confirmed last week that after several months of hunting their most wanted terrorist, the Pentagon did not realise that it had wounded him.

“We’ve had a number of close shaves but no evidence that we got him,” the official said. In February US troops near Ramadi received a tip-off about Zarqawi’s supposed movements and stopped what they believed to be his car at a roadblock. But reports last month said that Zarqawi had sent a decoy car ahead of the vehicle he was using precisely because he feared such a ploy.

When the decoy car was stopped, Zarqawi turned round and fled. By the time US troops caught up with his vehicle, he had vanished. But the troops recovered $100,000 in cash and a laptop computer that was said to contain key information about Zarqawi’s associates, several of whom were arrested.

There have been several fleeting glimpses since, but nothing as substantial as the account of Zarqawi’s appearance at the hospital in Ramadi.

“People here have obviously been speculating about whether that was really him at Ramadi,” the Washington official added. “But we’ve not been able to tie it down.”

Recent statements on militant websites and conflicting reports of Zarqawi’s injuries have provoked disagreement in Washington. The official said some analysts suspected a deliberate campaign of Al-Qaeda disinformation to cover Zarqawi’s escape, while others believed the group was preparing Arab opinion for an announcement of his death.

“If he’s got to Iran there’s not much we can do,” another official said. “Tehran is never going to admit he’s there and our intelligence is not exactly perfect in Iran.”

The insurgent commander insisted that Zarqawi would return to Iraq. “We would like to inform all Muslims and mujaheddin that the condition of our sheikh is stable and that he will soon return to pursue the path until the last American occupier is booted out,” he said.

Yet he also acknowledged that a “substitute” leader had been appointed to command Zarqawi’s group, named as Abu Hafs al-Qarni, an Al-Qaeda veteran who was born in Saudi Arabia and trained in Afghanistan under Bin Laden.

Qarni is said to be 33 years old and hiding on the Saudi Arabian side of Iraq’s long and desolate southern border. “The battle must have a commander and it is not right for an army to be leaderless,” the Iraqi commander said.

Despite the US portrayal of Zarqawi as a terrorist mastermind, neither US nor British officials expect his departure or death to make a difference to the continuing insurgency.

“The operational impact of his going will be pretty minimal,” said a senior Washington official. “He had the clout within Al-Qaeda to get the money and he tended towards the ‘spectaculars’ (the biggest atrocities) if he could, but the nuts and bolts of the day-to-day insurgency didn’t rely on him.”

Brigadier General Carter Ham, who earlier this year commanded US troops in Mosul, said Zarqawi’s demise would not halt the activities of Al-Qaeda in Iraq, which is believed by military intelligence to be organising many of the suicide bombings by foreign volunteers. “Whether he’s killed or captured, it won’t cause the organisation to necessarily crumble,” Ham said.

At the same time, officials argued, Zarqawi’s eclipse might have a longer-term impact on the recruitment of foreign suicide bombers, whose activities remain the greatest threat to Iraq’s civilian regime.

While intelligence sources believe that Zarqawi may have been responsible for only a fraction of the assaults for which his group has been blamed, he became a mythical figure for the young jihadists (holy warriors) who are praying for America’s defeat.

“Take him out of the equation and the jihadists may not be burning quite so fiercely to get themselves to Iraq,” one official said.