It is narrated from Sayyiduna Shaddad (may Allah be pleased with him); he said: In the time of the Conquest of Makkah, the Prophet (peace and blessings be upon him) saw a man being cupped when eighteen days of Ramadan had passed, and he (peace and blessings be upon him) said: "The one who cups and the one who is cupped have both broken their fast."
Hadith Referenceالمعجم الكبير للطبراني / باب الشين / 7097