Sayyiduna Ibn Abbas (may Allah be pleased with them both) narrates that the Prophet (peace and blessings be upon him) released the captives of Badr for ransom, and the ransom for each of them was four thousand (dirhams). Uqbah bin Abi Mu'ayt was killed before the ransom was taken: Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) rose to him and killed him while he was bound. He said: O Muhammad, what will become of (my) children? He (peace and blessings be upon him) said: "The Fire."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 12102