Silsilat al-Ahadith al-Sahihah

It is narrated from Sayyiduna Abu Hurairah, may Allah be pleased with him, that the Messenger of Allah, peace and blessings be upon him, said: "Whoever unjustly kills a confederate with whom a treaty has been made, will not even smell the fragrance of Paradise, and indeed, the fragrance of Paradise is perceived from a distance of one hundred years."