Grant Hodgson writes from Baghdad: I realised I had survived only when a mixture of coughs and sobbing filled the air.

I opened my eyes and, in the eerie half-light created by the bulbs on the television cameras, saw a scene of unforgettable carnage.

As the huge crash brought rubble down all around us, a stream of walking wounded stumbled into the Press room covered in a mixture of dust and blood.

Disorientated and with no lights to follow they desperately searched for an exit.

I took their hands and led them through the corridors of the UN headquarters at the Canal Hotel where I and a small group of journalists had gathered 30 minutes earlier for a routine briefing on landmines.

Some were bleeding heavily and could not walk.

I picked up one of the victims and put him over my shoulder, stumbling out of the building.

Each time I returned there were more. I carried six more people out, blood from their wounds soaking my own clothes.

Everywhere I turned, windows were smashed, rubble littered the floor and people were sobbing.

It was only when I sat down on the floor outside to catch my breath I realised the true scale of the blast.

Smoke poured into the air, forming a huge column before spreading like a mushroom cloud in the sky above.

Bloodied bodies lay on the grass. Some were with US army medics while others were unattended, already dead.

Many who were helped out into the daylight had been given makeshift bandages.

I was offered treatment but my gashed left leg was barely even an injury compared with the sheer carnage I could see all around me.

One man was carried away in a stretcher with an 18in metal bar speared through his face.

Another man's nose was hanging off. A third was walking around with a severed chin, asking: "Where am I?"

I could see one woman with blonde hair wearing a black T-shirt drenched in blood. She was face down and was not being treated - the medics scouring the area for those who could be saved had apparently decided she was beyond help.

A 20ft square area of grass was by now covered in blood-soaked bandages, dressings and water bottles.

US soldiers handed out water in a huge container. I helped fill empty bottles to give to those UN workers who needed it, many coughing up dust and some cleaning out deep wounds while they waited for medical assistance.

People were crying and hugging one another in shock and disbelief as the search for bodies under rubble continued.

Dead bodies were carried away to a makeshift morgue in a car park.

As I was ushered away from the scene I noticed debris close to the main entrance from the lorry in which the bomb was placed, a full 150 yards from the crater.

Only then did it really hit me: I was one of the lucky ones.