I stand in the shade outside the Catholic Church in Kisumu waiting for the march for peace to set off. It is my second day in Kenya where I am on commission for the London Evening Standard to cover the post-election violence.

My driver comes over to tell me that the protesters will march to the mortuary first to collect the victims of the violence. They will be taken in their coffins to the city's soccer stadium where opposition leader Raila Odinga will address the rally. Odinga is the leader of the OMD political party that lost to Mwai Kibaki in the disputed general election.

The march sets off on the half-mile walk to the mortuary. On the way we pass a workshop making coffins: there has been no shortage of trade in the last few weeks. Kisumu is located in the opposition heartland and there have been a large number of deaths. It seems to be impossible to get accurate figures for the number of people who have been killed. Some reports I've seen refer to 60 deaths but others speak of hundreds.

I'm ushered into the courtyard of the mortuary. The gate is quickly closed behind me to keep the marchers from pushing their way in. Outside, people have climbed on top of a truck and are shouting to be let in. Through the open doorway I can see six bodies being prepared for their coffins. I step inside; the cool green interior is a relief after being out in the tropical sun for a couple of hours. This is the first time I have seen a dead body. It is a young man in his mid-20s, naked, with a shaven head and small beard. He lies on his back on a chipped and dirty trolley, waiting to be dressed; the wall and floor are stained with blood. I take several photos although I know they will be too hard-core for the paper.

I move into a corridor where a young woman on a trolley is all dressed in white as if going for her first communion. Her face is puffy. I ask if she was shot. I am shown a large bullet hole in her upper arm, the flesh ragged and torn. I take more photographs. There is a nice sidelight and the background is good: a view into the room where they are putting the bodies into coffins and a door opening to the bright outside. The woman's family comes over to do a TV interview by her body and I move away.

The smell has started to get to me. I stand in the corner trying to take pictures that the newspaper can use. The corpses bend into a V shape when they are lifted by their hands and feet. Relatives carry the coffins outside. I look into a small alcove: three more bodies lay on the floor, naked, legs entwined.

Now all the coffins are lined up in the walled courtyard where a group of priests are trying to make themselves heard over the shouts of the crowd. It is a relief to be outside again, away from the smell. My writer comes over to tell me that there is a room with more bodies; he wants me to photograph it. I go back inside and ask to see the room.

I am taken to a sliding wooden door. Inside the room, a metal grill has been placed across two tables to support the dead, 10 in all. Each forehead has a label with 'unknown African' and a date. The room is not refrigerated; the bodies are swollen and the smell is overpowering. I walk around the table and find three more bodies on the floor. I struggle to think of a way of photographing the scene to make a picture that the paper can use. There is no clever way, so I just photograph it straight.

I go back outside as the gate swings open for the coffins to be taken to the stadium. I get in front of the first one as it passes through. As the crowd surges forward I am dragged backwards and some of the crowd start to turn on me. I quickly move to the edge of the mass and out of trouble.

As we march people rip branches from the trees that they then carry aloft as a sign of peace. We arrive at the stadium where the few police are quickly chased away by the crowd, who then turn on the school opposite with chants of "No Raila, no school." They chase the children away too.

I go into the stadium just as Raila Odinga's motorcade comes through the gate. I rush over and jump onto the running board of the first car, much to the surprise of the man on the other side. I can't really take pictures: I have to hang on while we bump along the dirt road around the stadium. When the crowd stops us, I jump off and run to the pickup truck in front of Odinga's car. A man is pushed from the packed truck and I'm pulled on board. With what feels like 20 pairs of hands holding on to me I manage to photograph Odinga's grand entrance into the stadium.

As the speeches start I manage to get myself to the front of the stand where the coffins have been placed. The crowd is packed in shoulder to shoulder. I worry that if I leave my spot I won't be able to get back. The speeches last for two hours, which I spend wedged in between a makeshift altar and the coffins. As I wait for the photo to happen I get a smell of the bodies drifting past. The rally comes to an end and people start to open the viewing windows in the coffins. This is the photo that I have been waiting for – it is the main picture used for the first of two double-page spreads that the paper runs.