Sayyiduna Abu Talhah (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) reached Khaybar in the morning. Those people were going out to their fields and lands with their spades and baskets. When they saw the Prophet (peace and blessings be upon him) with an army, they turned back on their heels. The Prophet (peace and blessings be upon him) said: "Allahu Akbar! Allahu Akbar! Khaybar is ruined! When we descend upon the courtyard of a people, evil is the morning of those who have been warned."
Ahmad and al-Tabarani recorded it with various chains, and the narrators of Ahmad are the narrators of the Sahih.
Hadith Takhrij«اخرجه الطبراني فى المعجم الكبير (4704) اخرجه احمد فى المسند (29/4) ، أخرجه سنن النسائي برقم: 3380، وأخرجه مسند أحمد برقم: 13360، 15915، وأخرجه المعجم الكبير للطبراني برقم: 4704»