Musnad Abu Ya'la al-Mawsili 134:16

Ibrahim ibn Sa'id al-Jawhari narrated to us, Abu Usamah narrated to us, al-A'mash informed us, he said: I was informed on the authority of Anas, who said: The Messenger of Allah (may Allah bless him and grant him peace) went out one night, and he intended to inform us about the Night of Decree (Laylat al-Qadr), and he had indeed informed us of it. Then he heard a clamor in the mosque, so it was snatched away from him.