Sahih Muslim Book 41, Hadith Number 6883.

Chapter : Not known.

Zainab bint Jahsh, the wife of Allah’s Apostle (may peace be upon him), reported that one day Allah’s Messenger (may peace be upon him) came out in a state of excitement with his face quite red. And he was saying: There is no god but Allah; there is a destruction in store for Arabia because of the turmoil which is near at hand as the barrier of Gog and Magog has been opened like it, and he (in order to explain it) made a ring with the help o his thumb and forefinger. I said: Allah’s Messenger, would we be destroyed despite the fact that there would be pious people amongst us? He said: Yes, when the evil would predominate.