Abd al-Rahman bin Ghanm narrates: Sayyiduna Abu Amir or Sayyiduna Abu Malik al-Ash'ari (may Allah be pleased with him) narrated to me - by Allah, he did not lie to me - that he heard the Messenger of Allah (peace and blessings be upon him) say: "There will certainly be people in my Ummah who will regard silk, wine and musical instruments as lawful. And some people will camp beside a mountain, with their livestock coming back to them in the evening. A man in need will come to them, and they will say to him: 'Come back to us tomorrow.' Then Allah, the Mighty and Majestic, will send punishment upon them by night and bring the mountain down upon them, and He will transform others into monkeys and pigs until the Day of Resurrection."
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 3404