Sahih Muslim Book 37, Hadith Number 6663.
Abu Sa’id al-Khudri reported Allah’s Messenger (may peace be upon him) as saying that a man killed ninety-nine persons and then he began to make an inquiry whether there was any way left for him for repentance. He came to a monk and asked him about that, and he said: There is no chance for repentance for you. He killed the monk also and then began to make an inquiry and moved from one village to another village where there lived pious persons, and as he had covered some distance, he was overtaken by death, but he managed to crawl upon his chest (to the side nearer to the place where the pious men lived). He died and then there was a dispute between the angels of mercy and the angels of punishment and (when it was measured) he was found to be nearer to the village where pious persons were living equal to the Space of a span and he was thus included among them.