This is his exclusive, eyewitness account:
"I had arrived in Ramallah at about 10.30 in the morning and was getting into a taxi on the main road to go to Nablus, where there was to be a funeral that I wanted to film, when all of a sudden there came a big crowd of Palestinians shouting and running down the hill from the police station.
I got out of the car to see what was happening and saw that they were dragging something behind them. Within moments they were in front of me and, to my horror, I saw that it was a body, a man they were dragging by the feet. The lower part of his body was on fire and the upper part had been shot at, and the head beaten so badly that it was a pulp, like red jelly.
I thought he was a soldier because I could see the remains of khaki trousers and boots. My God, I thought, they've killed this guy. He was dead, he must have been dead, but they were still beating him, madly, kicking his head. They were like animals.
They were just a few feet in front of me and I could see everything. Instinctively, I reached for my camera. I was composing the picture when I was punched in the face by a Palestinian. Another Palestinian pointed right at me shouting "no picture, no picture!", while another guy hit me in the face and said "give me your film!".
I tried to get the film out but they were all grabbing me and one guy just pulled the camera off me and smashed it to the floor. I knew I had lost the chance to take the photograph that would have made me famous and I had lost my favourite lens that I'd used all over the world, but I didn't care. I was scared for my life.
At the same time, the guy that looked like a soldier was being beaten and the crowd was getting angrier and angrier, shouting "Allah akbar" - God is great. They were dragging the dead man around the street like a cat toying with a mouse. It was the most horrible thing that I have ever seen and I have reported from Congo, Kosovo, many bad places. In Kosovo, I saw Serbs beating an Albanian but it wasn't like this. There was such hatred, such unbelievable hatred and anger distorting their faces.
The worst thing was that I realised the anger that they were directing at me was the same as that which they'd had toward the soldier before dragging him from the police station and killing him. Somehow I escaped and ran and ran not knowing where I was going. I never saw the other guy they killed, the one they threw out of the window.
I thought that I'd got to know the Palestinians well. I've made six trips this year and had been going to Ramallah every day for the past 16 days. I thought they were kind, hospitable people. I know they are not all like this and I'm a very forgiving person but I'll never forget this. It was murder of the most barbaric kind. When I think about it, I see that man's head, all smashed. I know that I'll have nightmares for the rest of my life.
That night when I got back to Jerusalem, I found out that I was the only photographer there and people kept asking me if I'd got the picture, then telling me I would have made my name.
I was so shocked that for the first time I didn't call my girlfriend who is back home in west London, five months pregnant with our first child. Of course, she was really worried because she'd seen on television what had happened and she knew that I was in Ramallah and then I hadn't called.
She was horrified and, when I did speak to her the next day, she asked: "Did you see?" I just said yes, but I couldn't really talk about it. Afterwards, I heard even worse details like that the policeman's wife was phoning his mobile to see if he was all right and them telling her that they were killing him. From what I saw, I can believe that.
I love this country, I'd love nothing more than to see Israelis and Palestinians sharing an argalah or waterpipe but, after the hatred that I've seen in the past few days, I don't think that will happen in my lifetime. Look how many years that they've been talking peace - since 1993. Then, within just a couple of weeks, they are at each other's throats. It seems that it's easier to hate than to forgive.
I didn't get the picture that would have made me famous but at least I am alive to see the birth of my child."