Over the last decade, more than four million people around the world have been killed in armed conflicts that were fueled with handheld weapons such as pistols, rifles, grenades and machine guns.

These small arms come from all over the world: Uzi's from Israel, AK-47's from the former Soviet bloc and American M-16's left over from the Vietnam War. They are passed from war zone to war zone through a global network of arms traffickers.

Liberian fighter. Photo: AP

Today, there are more than 550,000,000 small arms in circulation.

The United Nations has tried to stop the illegal weapons trade by imposing sanctions and embargos. But the arms keep coming. They are cheap and light-weight, easy to smuggle across borders in trucks and small planes.

This is a story about just one part of the illegal arms pipeline.