Musannaf Ibn Abi Shayba 3:977

Shababa narrated to us, he said: Shu'bah narrated to us, from Abu Bishr, from Abu Umayr ibn Anas, he said: My paternal uncles from the Ansar narrated to me, they said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "A hypocrite does not attend them," meaning the Isha and Fajr prayers.