Yahya related to me from Malik from Humayd at-Tawil from Anas ibnMalik that when the Messenger of Allah, may Allah bless him and granthim peace, went out to Khaybar, he arrived there at night, and when hecame upon a people by night, he did not attack until morning. In themorning, the jews came out with their spades and baskets. When theysaw him, they said, "Muhammad! By Allah, Muhammad and his army!" TheMessenger of Allah, may Allah bless him and grant him peace, said"Allah is greater! Khaybar is destroyed. When we come to a people, itis an evil morning for those who have been warned . "
USC-MSA web (English) reference: Book 21, Hadith 48
Arabic reference: Book 21, Hadith 1008