At least 132 students and nine staff members were killed on Tuesday when Taliban gunmen broke into a school in the Pakistani city of Peshawar and opened fire, witnesses said, in the bloodiest massacre the country has seen for years.
Wounded children taken to nearby hospitals said most victims died when gunmen, suicide vests strapped to their bodies, entered the compound and opened fire indiscriminately on boys, girls and their teachers.
"It was as though she was trying to wake him up to go school, as all mothers do every morning."
"Look, Zohra, look what they did to my son!" the woman said, and that's when I shot this picture.
It was among the first I took. It's not easy to photograph women in Pakistan, and Pashto women are very wary of strangers.
As soon as I reached their home, I had to ask the father's permission to take pictures. I then introduced myself to the mother - I wanted to make sure I was allowed to photograph her and that I would not be disturbing her.
The other women kept on just crying and paid no attention to me, so I stayed a little longer and shot some more photos.
It struck me how the mother was looking at her teenage son, and the expression on her mouth was as though she was trying to wake him up to go to school, as all mothers do every morning.
Seeing this was so painful. Any human, whether male or female, a parent or not, feels pain in their heart when they imagine what it's like to lose someone they love.
You can see how broken the woman is, and how heavy the moment I spontaneously shared with her was.
I've covered so many parents weeping over their children and it never gets easier. You have to feel their pain - it's almost as if their futures have been killed.