'Confirm. We have a T1 casualty, Tango 1. We need MERT now.'

That wasn't good. T1 meant we were losing him. He was critical. Flash was thinking the same as me. 'Where the hell is that Chinook!'

I got the empty case out of the weapon and was back in action.

'It's clear, Si!'

'I'll get the ammo. We need more ammo!' Si ran over to where John lay screaming and jerking about as if he was getting electric shocks. I scrambled onto my knees just as a three-round burst of Taliban fire hit the wall. I leant my chest into the mud bricks and got the weapon back into my shoulder. I never got to take aim, though. My rifle jolted skywards and a dark mass rose up from the other side of the wall.

Two large hands glued themselves to the front of my weapon. I tried to pull back but lost my footing, and a Tali the size of a house started to climb over the wall. He was using my rifle to help lever himself over.

As his feet inched higher up the wall, he pulled the barrel down hard onto his shoulder, the hot steel singeing the cloth of his shirt. He took no notice as the heat burnt through to his skin. The stench of sweat, cigarettes and burning flesh hit my nostrils, and within seconds the giant hands flailed out again, this time grabbing hold of my chest harness.

I scrambled backwards to escape his grasp, but he was quicker and stronger. He pulled me back towards the wall, trying to force me over with him. My helmet crashed into his head as I tried to headbutt him, but he took the pain and kept on pulling. I don't know what I shouted, but I yelled and screamed into his face as I butted him again, using all my body weight to stay on the right side of the wall. We were so close I could feel his beard scratch against my face. His spit sprayed into my eyes as he screamed back at me, his eyes fixed on mine.