Musannaf Ibn Abi Shaybah

Ibrahim, regarding the verse of the Holy Qur'an { وَإِنْ کَانَ مِنْ قَوْمٍ بَیْنَکُمْ وَبَیْنَہُمْ مِیثَاقٌ}, says: If a person becomes Muslim in the land of war and someone kills him, then there is no blood money upon him, only expiation.