"Finally, after Muhammad had attacked Mecca and won over the Quraysh tribes, he entered the Kaba and destroyed every icon or sculptured idol. According to some reports, Muhammad found Christian icons of Jesus, Mary, and Abraham that he did not destroy but left intact.
[After the conquest of Mecca] Apart from the icon of the Virgin Mary and the child Jesus, and a painting of an old man, said to be Abraham, the walls inside [Kaaba] had been covered with pictures of pagan deities. Placing his hand protectively over the icon, the Prophet told 'Uthman to see that all other paintings, except that of Abraham, were effaced. (Martin Lings, Muhammad: His Life Based on the Earliest Sources [Inner Traditions International, Ltd., One Park Street, Rochester, Vermont 05767; 1983], p. 300; ref.: al-Waqidi, Kitab al-Maghazi 834, and Azraqi, Akhbar Makkah vol. 1, p. 107)
... pictures of the prophets and pictures of trees and of angels. Among them there was a picture of Ibrahim as of an elderly man, drawing lots with arrow lots, and the picture of Jesus, the son of Mary, and of his mother and a picture with angels. (Al-Azraqi according to the Arabic text edited by Ferdinand Wuestenfeld, Chroniken der Stadt Mekka, Band 1, Leipzig 1858, reprint Beyrouth 1964, p. 110)
On the day of the conquest of Mecca the Prophet entered the House (= the Kaaba; my comment) and sent al-Fadl ibn al-Abbas ibn Abdalmuttalib to get water from the well of Zemzem. He ordered to bring pieces of cloth and to imbue them with water and then he commanded to wash off these pictures, as it was done. He stretched his arms, however, over the picture of Jesus, the son of Mary, and of his mother and said: 'Wash off all except what is under my hands!' But eventually he took away his hands away from Jesus, the son of Mary, and his mother. (Source: soc.religion.islam newsgroup posting)"
See
http://www.answering-islam.org/Shamoun/idolatry.htm