'Umar gained two lady captives from the war prisoners of Hunain and he left them in some of the houses at Makka. When Allâh's Messenger (ﷺ) freed the captives of Hunain without ransom, they came out walking in the streets. 'Umar said (to his son), O 'Abdullâh ! See what is the matter.". 'Abdullâh replied, "Allâh's Messenger (ﷺ) has freed the captives without ransom." He said (to him), Go and set free those two slave-girls." [4:372-O.B]