Musnad Abu Ya'la al-Mawsili 140:16

Abu Khaythama narrated to us, Hujayn ibn al-Muthanna narrated to us, Abd al-Aziz—meaning al-Majishun—narrated to us, from Muhammad ibn al-Munkadir, from Yazid al-Raqashi, from Anas ibn Malik, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "I asked my Lord regarding the *lahin* (those who are heedless/innocent) from the offspring of humans, that He not punish them, and He granted them to me."