The Odiham-based Chinook was called to help a patrol of paratroopers that had come under fire from Iraqi gunmen with rocket-propelled grenades and heavy machine guns.

The Kent-based paras returned fire but called for help after one was seriously injured and both their Land Rovers were destroyed.

When the Chinook arrived with a specialist rescue unit, the Iraqi gunmen opened fire again, shooting at the twin rotor helicopter. Six soldiers from 1 Para and an RAF reservist doctor on board were injured, three seriously.

But despite the heavy attack, the Chinook managed to fly the eight injured — one on the ground and seven in the helicopter — to a field hospital.

Two were transferred to a US field hospital in Kuwait for "specialist treatment for very serious injuries".

It is believed the wounded soldiers were due to fly home to their families within the next few days after a four-month tour of duty.

Miraculously, the four-man crew from Odiham — two pilots and two loadmasters — escaped injury.

Flt Lt Paul Smythe from RAF Odiham said the crew was extremely lucky not to get hit.

"The Chinook has bullet holes in it but it wasn't seriously damaged," he said. "It took the injured to hospital and then went on to land at Basra, where it remains at the moment. There will be an inquiry to find out exactly what happened and the aircraft will remain on the ground as part of the evidence into that inquiry."

Defence Secretary Geoff Hoon said an investigation is underway into whether the attack was related to another just two miles away when die-hard Fedayeen fanatics opened fire about 100 miles north of Basra, killing six British military police officers who had been trying to seize weapons from civilians.

It was the largest number of British personnel to be killed by hostile fire since the war began and the first deaths since April 6, bringing the total number of British troops killed to 43.

The Ministry of Defence said it would be conducting a review of the way British military operations are carried out in Iraq. There are likely to be questions about the British decision not to wear helmets or flak jackets in an effort to look less threatening and win friends in the local communities.

Mr Hoon told the Commons: "Coalition forces have worked hard to secure Iraq in the aftermath of decisive combat operations. They will not be deflected from their efforts by the enemies of peace."

Tony Blair's official spokesman said the Prime Minister heard the news with "great sadness" adding: "It goes without saying that he believes those who died have died with honour doing a very worthwhile job, serving their country with great distinction."

Crew from RAF Odiham will have a presence in Iraq for at least another two years.

During the war, Odiham's Chinooks put in more than 2,300 flying hours in the Gulf.

They helped in key areas, including supporting Royal Marines on the al-Faw peninsula in south eastern Iraq — seen by RAF Odiham crew as their finest hour during the conflict.

The Chinooks also helped capture the key port of Umm Qasr and supported 16 Air Assault Brigade in the Ramala oilfields.

Five RAF Odiham Chinooks are still in the Gulf helping in the humanitarian efforts.