Sahih al-Bukhari, Volume 5, Book 59, Hadith 582 (USC-MSA) ⓘ

Narrated Anas bin Malik: On the day of the Conquest, the Prophet entered Mecca, wearing a helmet on his head. When he took it off, a man came and said, "Ibn Khatal is clinging to the curtain of the Ka`ba." The Prophet said, "Kill him." (Malik a sub-narrator said, "On that day the Prophet was not in a state of Ihram as it appeared to us, and Allah knows better.")

حَدَّثَنَا يَحْيَى بْنُ قَزَعَةَ، حَدَّثَنَا مَالِكٌ، عَنِ ابْنِ شِهَابٍ، عَنْ أَنَسِ بْنِ مَالِكٍ ـ رضى الله عنه ـ أَنَّ النَّبِيَّ صلى الله عليه وسلم دَخَلَ مَكَّةَ يَوْمَ الْفَتْحِ وَعَلَى رَأْسِهِ الْمِغْفَرُ، فَلَمَّا نَزَعَهُ جَاءَ رَجُلٌ فَقَالَ ابْنُ خَطَلٍ مُتَعَلِّقٌ بِأَسْتَارِ الْكَعْبَةِ‏.‏ فَقَالَ ‏ "‏ اقْتُلْهُ ‏" ‏ قَالَ مَالِكٌ وَلَمْ يَكُنِ النَّبِيُّ صلى الله عليه وسلم فِيمَا نُرَى وَاللَّهُ أَعْلَمُ يَوْمَئِذٍ مُحْرِمًا‏.‏