Syrian photographer Hrair Sarkissian witnessed a public execution in Damascus as a young teenager on his way to school.
The memory of what he saw haunts him still, and drove him in 2008 to photograph squares in Syria where executions had taken place.
The photos are now on display in London’s Tate Modern gallery.
In this video, he shares his thoughts about the photos, and the challenges he faced taking them.
Read our Q&A with Hrair Sarkissian on "Execution Squares" here.