Question 598: Salam. How many zio-Muslim pagans from the army of satan (yazeed son of Moawia) were sent to hell by Imam Hussain a.s before embracing martyrdom? How many Enemies killed by Imam Hussain (as) in Karbala on the Day of Ashura?
Answer 598: Some narrators said: when Imam Hussain became alone on the Day of Ashura, we, the narrators swore by Allah that there was no one braver than him, because his children, families and companions have been killed, but when the enemies attacked Him He attacked them all too. He himself attacked the whole enemies in a way that they were all running away from Him like locust, He then came back to his military base saying: La Hawla wa la Quwwata illa billah al-Ali al-Adhim.
In Ithbat al-Wasiyya there is a tradition in which mentioned that 1800 fighters, the infidels have been killed by Imam Hussain (as) on the Day of Ashura.
In Bihrar al-Anwar ibn Shar Ashub and Muhammad bin Abi Talib narrated: The Imam (as) has been continuously attacked and finally single-handedly killed 1,950 infidels in Karbala. And then Umar bin Sa’ad shouted at his army and said: Woe is to you! Do you know with whom you are fighting? He is the son of Qattal al-Arab! Attack him from all sides. And then Four thousands fighters surrounded him and close the way toward his tents.
In response to this question that how is it possible that the Imam (as) can kill the number of infidels, we should say that since the army of Umar Sa’ad were afraid of the Imam’s fighting they were running away from Him in order to save their lives. So, some of them have been killed under the hands and feet of horses and the crowd of people and therefore, the dead were too much in number.
The Arabic version of this narration is as follows:
قال بعض الرواة فو الله ما رأيت مكثورا قط قد قتل ولده و أهل بيته و صحبه أربط جأشا منه و إن كانت الرجال لتشد عليه فيشد عليها بسيفه فتنكشف عنه انكشاف المعزى إذا شد فيها الذئب و لقد كان يحمل فيهم و قد تكملوا ألفا فينهزمون بين يديه كأنهم الجراد المنتشر ثم يرجع إلى مركزه و هو يقول لَا حَوْلَ وَ لَا قُوَّةَ إِلَّا بِاللَّهِ الْعَلِيِّ الْعَظِيمِ.
و قال ابن شهرآشوب و محمد بن أبي طالب و لم يزل يقاتل حتى قتل ألف رجل و تسعمائة رجل و خمسين رجلا سوى المجروحين فقال عمر بن سعد لقومه الويل لكم أ تدرون لمن تقاتلون هذا ابن الأنزع البطين هذا ابن قتال العرب فاحملوا عليه من كل جانب و كانت الرماة أربعة آلاف فرموه بالسهام فحالوا بينه و بين رحله.
For further information in this regards, please refer to the following answer:
 . Ithbat al-Wasiyya, Al-Mas’udi, Pg. 168.
 . Bihar al-Anwar, Vol. 45, Pg. 50.