حَدَّثَنَا الْحَسَنُ بْنُ عَلِيٍّ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم نَحْوَهُ قَالَ ‏:‏ ‏"‏ سِيمَاهُمُ التَّحْلِيقُ وَالتَّسْبِيدُ، فَإِذَا رَأَيْتُمُوهُمْ فَأَنِيمُوهُمْ ‏"‏ ‏.‏ قَالَ أَبُو دَاوُدَ ‏:‏ التَّسْبِيدُ اسْتِئْصَالُ الشَّعْرِ ‏.‏

The tradition mentioned above has also been transmitted by Anas through a different chain of narrators in a similar manner. This version adds; Their sign is shaving the head and eliminating the hair. If you see them, kill them. Abu Dawud said: Tasmid means uprooting the hair. Translation Not Available

Book Ref: Sunan Abi Dawud Book 42 Hadith 4766
Web Ref:  Sunan Abi Dawud Book 41 Hadith 4748