With minor differences in narrations, Tareekh-e-Tabari, Tareekh-e-Yaqoobi, Shaikh Mufeed’s (a.r.) Irshaad and Tabaqaat-e- Ibn-e-Saad have narrated the occurrence. Balazari and Waaqedi too have recorded the same.
The summary of all accounts is that when the bloody battle of Naharwaan came to an end, a few Khawaarij got together to mourn the dead.
Their grief was compounded with their remembrance of the worship, obedience and piety of the deceased.
They blamed three people for their sorrow:
(a) Imam Ali (a.s.),
(b) Amr-e-Aas and
(c) Muawiyah Ibn Abi Sufyan
They felt that as long as these three were alive, the Muslim nation wouldn’t reform.
Consequently, three people took the responsibility of assassinating Imam Ali (a.s.), Amr-e-Aas and Muawiyah on their shoulders.
1. Abd al-Rahman Ibn Muljim (may Allah curse him and subject him to the severest of humiliations) took the responsibility of martyring Imam Ali (a.s.)
2. Barq Ibn Abdullah took the responsibility of eliminating Muawiyah
3. Amr Ibn Bakr al-Tameemee took the responsibility of getting rid of Amr Ibn Aas
They thought, “To execute this plan, the holy month of Ramazan should be chosen because these three persons frequent the mosque in this month.”
The dates fixed were the nights of 11, 13 or 17. According to Shiite records, the eve of nineteenth (19) was chosen. The reason for preferring these nights was because these three persons were expected to be in the mosque.
Anyway, the person who had taken the responsibility of killing Amr Ibn Aas killed the person who had come to lead the prayers instead.
The sword of the one who was responsible to slay Muawiyah, struck his thigh. Muawiyah got injured but after some medication, recuperated.
It was only Ibn Muljim (l.a.) who succeeded in executing his nefarious intentions!!
Is this murder story true or there is more than meets the eye?
In other words, is the story related about the martyrdom of Imam Ali (a.s.) really true?
The reply is that ‘the story is untrue’ and right from the onset there were clear indications that the story was fabricated.
Expert historians have speculated and written that these three visited the mosque in Ramazan and their coming to the mosque on the night 19 Ramazan was a certainty.
There’s no doubt that Ameer al-Momineen Ali (a.s.) was struck on the head by Ibn Muljim (l.a.) on the night of 19th Ramazan. But why did the one who went to kill Amr-e-Aas instead kill the one whose name was Kharjah? Was it that the person who went to slay Amr-e-Aas wasn’t aware who he was or did not recognize him? Or why did Amr-e-Aas not show up in the mosque that night? Was he warned or informed of the conspiracy?
The best way to dig out facts in this regard is to scrutinize the whole conspiracy closely because the net of this wicked plot was cast from Kufa to Damascus. As has been reported, Muawiyah was aware that as long as Imam Ali (a.s.) was alive it was not possible for him to attain Caliphate.
Ash’ath Ibn Qais (l.a.), as is well-documented, was a notorious hypocrite and not inwardly satisfied with Ameer al-Momineen Ali (a.s.).
Ibn Abi al-Dunya (d. 281 A.H.) in his book ‘Maqtal-e-Imam Ameer al-Momineen Ali Ibn Abi Taalib (a.s.) (it is worth noting that this book is older than the records of Tabari and Yaqoobi) has narrated on the authenticity of his chain of narrators through Abd al-Ghaffar Ibn Qasim Ansari that:
“I have heard from many people that Ibn Muljim (l.a.) was with Ash’ath (l.a.) on that fateful night (19th of Ramazan) and at the break of dawn, he told him ‘the dawn has arrived.'”
If these three were the only ones involved in the conspiracy then what was Ibn Muljim (l.a.) doing with Ash’ath (l.a.) in the mosque? Why were they talking there?
Is it expected of a man, who is on a secret mission to kill Imam Ali (a.s.), reveal his plans to another person (and that too to a person like Ash’ath (l.a.))?!!
Balaazari has narrated this in ‘Ansaab al-Ashraaf‘:
“They say Ibn Muljim was with Ash’ath bin Qais (l.a.) that night. They were talking in a hush-hush tone till Ash’ath (l.a.) said to Ibn Muljim (l.a.), ‘Get up, the morn is here.’ (Hurry lest people will recognize you in the daylight). When Hujr Ibn Adi heard his talk, he said, ‘O one-eyed! You have killed him (a.s.).'”
The narrators have also reported that when Ibn Muljim (l.a.) had struck the sanctified head of Imam Ali (a.s.) with his sword, Ash’ath (l.a.) then sent his son to Imam Ali (a.s.)’s house to assess Imam’s (a.s.) condition.
He came back and related, “His [Imam Ali (a.s.)] eyes have sunk in.” On hearing this, Ash’ath (l.a.) remarked, “By Allah! The eyes show that the poison has reached his brain.”
Like historians Maa’sir Abaazi, Shaikh Sulayman Yusuf Ibn Dawood, I am not going to say that the Khawaarij were friends of Imam Ali (a.s.) and they were not party to his assassination.
The reason being, the tribe of Bani Murad, to which Ibn Muljim (l.a.) belonged, is not enlisted with the ‘Khawaarij.’ The story of Ibn Muljim (l.a.) and the other two failed assassins has been fabricated and paid for in Muwaiyah’s factory of lies and deceit to conceal the truth from the people.
But the fact remains that if anyone says that the famous conspiracy spun around the martyrdom of Imam Ali (a.s.) is not the true one, then I don’t consider his thoughts to be far from the truth.
If looked closely, I reiterate, the fact remains that one end of the thread of this conspiracy starts from Ash’ath bin Qais (l.a.) in Kufa and ends in Damascus with Muawiyah.
As we have mentioned earlier, Ash’ath (l.a.) was unhappy with Imam Ali (a.s.) as Imam (a.s.) had dismissed him from the government and had even introduced him as a hypocrite and son of an unbeliever.
Shahrastani, the renowned historian, writes: “Among those who rebelled against Imam Ali (a.s.), Ash’ath (l.a.) was in the forefront. He was harsh and the first to break away from religion.”
 Ansaab al-Ashraaf, p. 493
 Maqtal al-Imam Ameer al-Momineen (a.s.), p. 37; Tabaqaat Ibn Saad, vol. 3, p. 37
 Al-Melal wa al-Nehal, vol. 1, p. 170; Ali Az Zabaan Ali or Zindagaani Ameer al-Momineen (a.s.), p. 157; Dr. Syed Ja’far Shaheedi, narrated from Khabar Guzaari Shabistaan