The Prophet ﷺ said: Soon there will appear disagreement and dissension in my people; there will be people who will be good in speech and bad in work. They recite the Qur'an, but it does not pass their collar-bones. They will swerve from the religion as an animal goes through the animal shot at. They will not return to it till the arrow comes back to its notch. They are worst of the people and animals. Happy is the one who kills them and they kill him. They call to the book of Allah, but they have nothing to do with it. He who fights against them will be nearer to Allah than them (the rest of the people). The people asked: What is their sign? He replied: They shave the head. (Using translation from Abū Dāʾūd 4765)
أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ «سَيَكُونُ فِي أُمَّتِي اخْتِلَافٌ وَفُرْقَةٌ قَوْمٌ يُحْسِنُونَ الْقِيلَ وَيُسِيئُونَ الْفِعْلَ وَيَقْرَءُونَ الْقُرْآنَ لَا يُجَاوِزُ تَرَاقِيَهُمْ يَمْرُقُونَ مِنَ الدِّينِ مُرُوقَ السَّهْمِ مِنَ الرَّمِيَّةِ لَا يَرْجِعُونَ حَتَّى يُرَدَّ عَلَى فَوْقِهِ شَرُّ الْخَلْقِ وَالْخَلِيقَةِ طُوبَى لِمَنْ قَتَلَهُمْ وَقَتَلُوهُ يَدْعُونَ إِلَى كِتَابِ اللَّهِ وَلَيْسُوا مِنْهُ فِي شَيْءٍ مَنْ قَاتَلَهُمْ كَانَ أَوْلَى بِاللَّهِ مِنْهُمْ» قَالُوا يَا رَسُولَ اللَّهِ فَمَا سِيمَاهُمْ؟ قَالَ «التَّحْلِيقُ» لَمْ يَسْمَعْ هَذَا الْحَدِيثَ قَتَادَةُ مِنْ أَبِي سَعِيدٍ الْخُدْرِيِّ إِنَّمَا سَمِعَهُ مِنْ أَبِي الْمُتَوَكِّلِ النَّاجِيِّ عَنْ أَبِي سَعِيدٍ