Musnad Abu Ya'la al-Mawsili 118:4

Narrated to us Mansur ibn Abi Muzahim, narrated to us Malik ibn Anas, from al-Zuhri, from Anas ibn Malik, that the Prophet, peace and blessings of Allah be upon him, entered on the day of the Conquest, and upon his head was a helmet. It was said, "This is Ibn Khatal, clinging to the curtains of the Kaaba." He said, "Kill him."