It is narrated from Sayyiduna Imran bin Husayn al-Khuza'i (may Allah be pleased with him) that a man freed six slaves during his illness, "so the Prophet (peace and blessings be upon him) cast lots between them, freed two, and kept four in slavery."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 15452