Allah’s curse is on the one who frightens the people of Madina
Yazid ordered the ravaging of Madina and public killings although there are severe warnings in Hadith for those who just frighten the people of Madina. There is a Hadith in Musnad Ahmed, Hadith No. 15962:
Translation: It is narrated on the authority of Hadhrat Saib bin Khallad (May Allah be well pleased with him) that the Holy Prophet (Sallallahu alaihi wa sallam) said: Whoever frightens the people of Madina by their oppression, Allah will frighten him and on him rests the curse of Allah, of the angels and of all the people. Allah Most High will not accept any obligatory (Fardh) or supererogatory (Nafl) act from such a person on the Day of Judgment. (Tarikh Ul Khulafa, Pg No. 167)
It can be imagined what will be the lot of the person who not only frightened the people of Madina but spilled blood and ravaged Madina and gave permission to the whole army for their animalistic deeds.