Teenager Talir Munir Paracha uploaded these pictures to Facebook earlier this week.
Paracha is on the first left. He and his friend Hassan Javed Khan (second right) both managed to escape from the gunmen who killed more than 150 people after attacking a school in Peshawar.
On the second left of the bottom picture is Rafiq Bangash and on the far right is Mohammad Yassen: neither of them were able to escape the terrorists.
Yassen was a keen amateur photographer.
Shortly after his death, his British cousin paid tribute to him.
He told MailOnline:
Muhammed was very keen on cricket and cars and had recently taken up photography. On Sunday he posted a very poignant selfie which looked like he had turned his back to us. He Facebooked me over the weekend because I had posted a funny video on my page and he 'liked' it. He wrote 'lol' and a few smiley faces.'It hasn't sunk in that I won't speak to him or hear from him again.
Yesterday teachers returned for the first time to the school: there has been an extended break across the country following the massacre.