Here scan of hadith from “az-Zunub al-Kabera” (2/324) of Ayatolla Dastagheyb:

 إِذَا رَأَيْتُمْ أَهْلَ الرَّيْبِ وَ الْبِدَعِ مِنْ بَعْدِي فَأَظْهِرُوا الْبَرَاءَةَ مِنْهُمْ وَ أَكْثِرُوا مِنْ سَبِّهِمْ وَ الْقَوْلَ فِيهِمْ وَ الْوَقِيعَةَ وَ بَاهِتُوهُمْ كَيْلَا يَطْمَعُوا فِي الْفَسَادِ فِي الْإِسْلَامِ وَ يَحْذَرَهُمُ النَّاسُ وَ لَا يَتَعَلَّمُوا مِنْ بِدَعِهِمْ يَكْتُبِ اللَّهُ لَكُمْ بِذَلِكَ الْحَسَنَاتِ وَ يَرْفَعْ لَكُمْ بِهِ الدَّرَجَاتِ فِي الْآخِرَةِ

Translation:

When you after me find people of bid’ah and doubt/suspicion, do disassociation from them and increase your insults to them and accuse them of false things, and oppose them so they may not become greedy in bringing corruption in Islam. You must warn people against them and against learning their bid’ah (innovations). Allah will reward you for this and will raise you darajaat (positions) in the next life.

So these shias taught by their books to abuse each and everyone which is innovator in their view!