When the Messenger of Allah ﷺ set out for Khaybar, he arrived there at night. It was his practice that whenever he came upon a people by night, he would not launch an attack until morning. The Jews came out with their spades and baskets, and when they saw him they cried out, "Muhammad, by Allah, Muhammad and his army!"The Messenger of Allah ﷺ said, "Allah is the greatest! Khaybar is ruined. When we descend upon the courtyard of a people, evil is the morning of those who were warned."
أن رسول الله ﷺ حين خرج إلى خيبر، أتاها ليلا، وكان إذا أتى قوما بليل لم يغر حتى يصبح، فخرجت يهود بمساحيهم ومكاتلهم، فلما رأوه قالوا: محمد، والله محمد والخميس، فقال رسول الله ﷺ: الله أكبر! خربت خيبر، إنا إذا نزلنا بساحة قوم، فساء صباح المنذرين.
Malik narrated it in jihad (48), from Humayd Tawil, from Anas bin Malik, and he mentioned it.Bukhari also narrated it in Maghazi (4197), via Malik, with similar wording.