Sayyiduna Abdullah bin Amr (may Allah be pleased with him) said: The son of Adam (peace be upon him) who killed his brother will share with the people of Hell half of their punishment, an exact division.
Al-Bazzar recorded it, and its narrators are the narrators of the Sahih, except that I have not seen anyone who has written a biography of al-Bazzar's teacher Abdullah bin Ishaq al-Attar; he narrates from Affan.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب العلم / 774