Abu Qatādah al-Ansāri (may Allah be pleased with him) reported: We went out with the Prophet (may Allah's peace and blessings be upon him) to Hunayn. He narrated a story. Then, the Prophet (may Allah's peace and blessings be upon him) said: "Whoever kills someone in battle, having a proof for that, his belongings are his." He said it three times. Authentic hadith - Narrated by Bukhari & Muslim