@Khaqani_M shared the an interesting picture (below) showing the guidance on battlefield rules issued a few days ago by Shi’i marja’ Ayatollah Ali al-Sistani spreading amongst fighters engaged in the Fallujah operation.
What follows is a rough translation of this guidance with the original Arabic text below:
“So it comes to the fight with those wicked ones who left the path of Islam and those warriors from the Muslims and their striking – morally and ethically – in the manner passed down from the Imam Ali (peace be upon him) and how he acted in such situations which unfolds in his life and which he recommended to his companions through his sermons and sayings, and the ummah had gathered to receive them and made of them a proof between themselves and God. Therefore, they are beholden to follow this example and adopt this approach, for he had said (peace be upon him) in his speech, confirming what is reported of the Prophet (blessings of God upon him and his family) – in the Hadith al-Thaqalayn (‘the two weights’) and al-Ghadir (the Hadith of Ghadir Khumm) and others.
Jihad has general rules that must be adhered to even with the non-Muslims, and the Prophet (blessings of God upon him and his family) advised his companions of these rules before sending them to fight, and this was borne out by Imam al-Sadiq (peace be upon him) saying: “The Prophet, blessings of God upon him and his family) wanted to send forth a company, he called them and had them sit by him, then he said: march in the name of God and walk in his path and the creed of the Prophet of God (blessings of God upon him and his family): do not be extreme and act out of hatred, do not deceive or betray, do not kill an old man or a young boy or women, do not cut down a single tree unless you are forced to.”