Mishkat al-Masabih 21 Foods كتاب الأطعمة 20

وَعَن عَمْرو بنِ أُميَّةَ أَنَّهُ رَأَى النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يحتزمن كتف الشَّاة فِي يَدِهِ فَدُعِيَ إِلَى الصَّلَاةِ فَأَلْقَاهَا وَالسِّكِّينَ الَّتِي يَحْتَزُّ بِهَا ثُمَّ قَامَ فَصَلَّى وَلَمْ يتَوَضَّأ

‘Amr b. Umayya told that he saw the Prophet cutting slices from a shoulder of mutton in his hand. He was summoned to prayer, and after throwing it and the knife with which he was slicing it away, he stood up and prayed without performing ablution. (Bukhari and Muslim.)