Sahih Bukhari Volume 009, Book 088, Hadith Number 248.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 88. Afflictions and the End of the War
Narrated By Anas bin Malik : The Prophet said, "Ad-Dajjal will come to Medina and find the angels guarding it. So Allah willing, neither Ad-Dajjal, nor plague will be able to come near it."