A boy clowning around on a basketball court in a Colombian cocaine corridor: Mads Nissen’s best photograph

‘I took this in 2017, when Didiller was nine.

A few years ago, I returned to the area and asked about him, but couldn’t find him.

Someone told me he had been killed’

I fell in love with photography when I was 19, while studying Spanish and doing voluntary work in Venezuela.

Having grown up in the quite boring countryside of Denmark, I was curious about the rest of the world and had become socially and politically engaged.

Walking down a street in Mérida with an old camera in my hand, I realised this was the perfect medium to push for the values I believed in, to try to make a change in the world.

This was when I also became fascinated by the neighbouring country of Colombia, where civil war was causing great instability.

I would later travel there for a project about the Amazon rainforest, and in 2016 I was commissioned by the Nobel Peace Center to cover the final stages of the peace process.

I also focused on the millions of people who had been displaced within the country due to the conflict, but it felt like I couldn’t talk about turmoil and inequality in Columbia without looking at how its problems were influenced by the country’s production of cocaine.