I have heard the Messenger of Allah ﷺ say: Different evils will make their appearance in the near future. Anyone who tries to disrupt the affairs of this Umma while they are united you should strike him with the sword whoever he be. (If remonstrance does not prevail with him and he does not desist from his disruptive activities, he is to be killed.)  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ إِنَّهُ سَتَكُونُ هَنَاتٌ وَهَنَاتٌ فَمَنْ أَرَادَ أَنْ يُفَرِّقَ أَمْرَ هَذِهِ الْأُمَّةِ وَهِيَ جَمِيعٌ فَاضْرِبُوهُ بِالسَّيْفِ كَائِنًا مَنْ كَانَ  

" Kill him."  

عَنِ النَّبِيِّ ﷺ بِمِثْلِهِ غَيْرَ أَنَّ فِي حَدِيثِهِمْ جَمِيعًا فَاقْتُلُوهُ  

" Kill all of them." I heard the Messenger of Allah ﷺ say: When you are holding to one single man as your leader, you should kill who seeks to undermine your solidarity or disrupt your unity.  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ مَنْ أَتَاكُمْ وَأَمْرُكُمْ جَمِيعٌ عَلَى رَجُلٍ وَاحِدٍ يُرِيدُ أَنْ يَشُقَّ عَصَاكُمْ أَوْ يُفَرِّقَ جَمَاعَتَكُمْ فَاقْتُلُوهُ