From Sahih Bukhari (Hadith 3598):
Narrated Zainab bint Jahsh:That the Prophet (ﷺ) came to her in a state of fear saying, "None has the right to be worshiped but Allah! Woe to the Arabs because of evil that has come near. Today a hole has been made in the wall of Gog and Magog as large as this." pointing with two of his fingers making a circle. Zainab said, "I said, 'O Allah's Messenger (ﷺ)! Shall we be destroyed though amongst us there are pious people? ' He said, 'Yes, if evil increases
Reference: Bukhari 3598