Musannaf Ibn Abi Shayba 18:1014

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Salamah ibn Nabit narrated to us, from al-Dahhak: "And whoever kills a believer intentionally, his recompense is Hell, wherein he will abide eternally." He said: Nothing has abrogated it since it was revealed.