Burhan Khan can't remember exactly when he fled from Afghanistan to Pakistan. He thinks it was about 30 years ago.
"Because there was war. There was killing, there was murdering, there was firing, and they wanted to kill me, and they wanted to kill my children, so I had to come here," he says.
It was the final phase of the Cold War, and CIA-armed Afghan guerrillas were fighting to drive the Soviets out of Afghanistan.
Khan and his family wound up where they are today, in a mud hovel on a patch of wasteland outside Pakistan's capital, Islamabad.