Sahih Bukhari Volume 004, Book 056, Hadith Number 702.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 56. Virtues and Merits of the Prophets (PBUH) and his Companions
Narated By Abi Mas'ud : The Prophet said, "From this side from the east, afflictions will appear. Rudeness and lack of mercy are characteristics of the rural bedouins who are busy with their camels and cows (and pay no attention to religion). Such are the tribes of Rabi'a and Mudar."