Asmāʾ bint Marwān and Abū ʿAfak

There was a woman called Asmāʾ bint Marwān. This woman was gathering people to fight against the Muslims, and she would spread lies about the Muslims. So a man called ʿUmayr ibn ʿAdī al-Khaṭmī killed her. He went to the Messenger of Allah (peace be upon him) and said, "Is that what I did wrong?" The Messenger of Allah (peace be upon him) told him, "You have assisted Allah and His Messenger, O ʿUmayr" — and the Messenger of Allah (peace be upon him) said, "No two rams will butt heads over this," meaning that this is an issue over which there should be no dispute: what he did was right.

Abū ʿAfak, a Jewish man, was also inspiring others to fight against the Muslims. The Messenger of Allah (peace be upon him) said, "Who will rid us of Abū ʿAfak?" — and he too was assassinated by the Muslims because of his evil.

But the most famous assassination of all was that of Kaʿb ibn al-Ashraf, and his story is famous in Ṣaḥīḥ al-Bukhārī; it is also narrated by Ibn Isḥāq and other scholars.