Hadith 31-278

وَبِإِسْنادِهِ عَنْ عَلِيِ‏ عَلَيْهِ السَّلامُ قالَ: قالَ النَّبِيُ‏ صَلَّى اللهُ عَلَيْهِ وَآلِهِ: يَقْتُلُ الحُسَيْنَ شَرُّ الاُمَّةِ، وَيَتَبَرَّأُ مِن وُلْدِهِ مَن يَكفُرُ بي.

According to the same documentation, on the authority of Ali (a.s.), the Prophet (S) said, “The most wicked member of this nation will kill Al-Husayn (a.s.). Whoever denounces Al-Husayn’s (a.s.) progeny has denounced me.”