Musannaf Ibn Abi Shayba 28:898

'Abdullah ibn al-Mubarak narrated to us, from Ma'mar, from Ziyad ibn Muslim, that a man from the people of India arrived in Aden under a guarantee of safety (aman), and a man from the Muslims killed him in retaliation for his brother. He wrote regarding that to 'Umar ibn 'Abd al-'Aziz. He wrote back: "Do not kill him, but take the blood money (diyah) from him and send it to his heirs." And he ordered that he be imprisoned.