Allah's Curse Is On The One, Who Frightens The People Of Madina
Yazid ordered the ravaging of Madina Munawwarah, public killings, when there are severe warnings in Hadith for those just who frighten the people of Madina Munawwarah. There is a Hadith in Musnad Ahmed, Musnad madaniyyen Hadith No. 15962.
Translation: It has been narrated on the authority of Hadhrat Saib bin Khalad (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 will not accept any obligatory (Fardh) of optional (nafl) act from such a person the Day of Judgment.
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.
Yazid's Army Stoned The Ka'aba
Afterwards, Yazid ordered the army to attack the Ka'aba in Makkah. Accordingly, Yazid's army set up their cannons and stoned the Ka'aba, because of which the curtain of the Ka'aba caught fire.
It is written in Tarikh Kamil, Vol 3, Pg. No. 464,
"To the extent that when 3 days of Rabe'e ul Awwal passed, they stoned the Ka'aba with their cannons, burnt it and started singing thus: "We have tremendous power and courage, we stone this Masjid with cannons."
In the basic tract of beliefs (Aqaaid), which is taught in most Madrasas, Sharh Aqaaid Nasafi, Imam Sa'aduddin Taftazani (May Allah shower His Mercy on him) writes: Some Imams, because of ordering the martyrdom of Imam Hussain, declare him as a disbeliever (kafir) and defector (murtad), and hold cursing Yazid as permissible. The scholars of this Ummah are in agreement on the permissibility of cursing those martyred Imam Hussain and those who ordered it or those consider it (the martyrdom) as permissible and those who became happy on it. The fact is that Yazid's agreement on the martyrdom of Imam Hussain, his being happy with it and his insulting the Ahle Bait is well established by those traditions, which are in effect, equal to the "mutawatir" (popular) Traditions, even though its details may not be established by a first-hand report (Khabr Wahid). So we cannot exercise restraint on Yazid, but we will exercise restraint about the Iman of Yazid. May Allah curse him and his helpers.