A short time after the Raj’i incident (4 Safar/July 625), chief of the Amir ibn Sa'sa' tribe Abu Bara' Amir ibn Malik came to Madina and obtained information about Islam from Prophet Muhammad. Despite not being Muslim himself, he requested that the Prophet send representatives to his tribe to teach them about Islam. After receiving assurances of their safety, the Prophet assigned a group of seventy (or forty) people well-versed in the Qur’an, most of them natives of Madina and People of the Suffa, led by Mundhir ibn 'Amr al-Khazraji. When the group arrived at Bi'r Al-Mauna, on the road between Makka and Madina, the Prophet’s Companion Haram ibn Milhan was given the responsibility of taking Prophet Muhammad’s letter to the chief of the Amir ibn Sa'sa' tribe. Meanwhile, upon receiving news that Amir ibn Malik had died, Haram ibn Milhan gave the letter to the former’s nephew Amir ibn Tufayl and invited those around him to Islam. Just as longtime, avowed enemy of Prophet Muhammad and the Muslims, Amir ibn Tufayl, had the envoy killed, he incited members of the tribe to launch an attack on the Muslims at Bi'r Al-Mauna. However, the people did not respond positively to this proposal due to the fact that Amir ibn Malik had guaranteed the safety of members of the delegation. Amir ibn Tufayl then appealed to certain branches of the Banu Sulaym tribe with whom they had bonds of friendship. With his provocation, armed groups from the neighboring tribes attacked the Muslims waiting at Bi'r Al-Mauna and completely unaware of any of these developments. They killed everyone except Ka’b ibn Zayd al-Najjar, who was severely wounded and left for dead, and Mundhir ibn Muhammad (or Harith ibn Thimma), who had taken the camels out for pasture at the time, and ‘Amr ibn Umayya. Unable to bear what had happened to his friends, Mundhir ibn Muhammad attacked the polytheists and was also killed. When ‘Amr ibn Umayya, who was taken as prisoner, said that he was from the tribe of Mudhar, he was released by Amir ibn Tufayl to fulfil his mother’s votive offering of emancipating a slave.
Learning of this horrific incident by means of revelation and informing his Companions therein, Prophet Muhammad felt more pain and sorrow than ever before and cursed those responsible for this incident during every morning prayer for thirty or forty days on end. He sent a force of 24 men under the command of Shuja’ ibn Wahb, with the purpose of punishing the Amir ibn Sa'sa' tribe who were responsible for the Bi'r Al-Mauna massacre (8 Rabi` al-Awwal/July 629). Many animals were taken as booty and women captured in a sudden night raid. Some time later, a Muslim delegation from the Banu Amir ibn Sa'sa' came to Prophet Muhammad and requested that the women taken captive be released. Consulting with Shuja’ ibn Wahb and his Companions, the Prophet released the women upon their acceptance of Islam.