Joel made a break for it the same day that Amber wrote the last letter. He made it as far as the wire before the bullets dragged him down. His right arm was thrust through the wire fence and holding his right hand with her own was Amber.
When she caught sight of Joel's approaching figure Amber ran as fast as she could towards the fence, dragging Kate along with her. The bullet that struck Kate killed her instantly. Amber was not killed by those inside but by her fellow exiles who hurled anything that could be thrown towards her back. A sharp rock that struck the back of her head delivered the killing blow.
Did Amber's father feel remorse or grief at her death? No, he did not. Already very sick with the fever he seemed totally unaware of what had happened to his daughter, even though he had stood throwing missiles with the rest of them. He died within two days of Amber and none of the exiles survived for more than a week after that.
Nobody ever seemed to discover who was in charge of the takeover of Mortown. Nobody ever found out the reason for exiling so many inhabitants. If it was an attempt to keep out the sickness it was a failed one. Every inhabitant inside the wire was dead within a month.