Sahih Muslim Book 54, Hadith 1

There is no being worthy of worship except Allah; there is a destruction in store for Arabia because of turmoil which is at hand, the barrier of Gog and Magog has opened so much. And Sufyan made a sign of ten with the help of his hand (in order to indicate the width of the gap) and I said: Allah's Messenger, would we be perished in spite of the fact that there would be good people amongst us? Thereupon he said: Of course, but only when the evil predominates.