ENOfficial
Narrated Nafi`: Ibn `Umar informed me that on the day (of Mu'tah) he stood beside Ja`far who was dead (i.e. killed in the battle), and he counted fifty wounds in his body, caused by stabs or strokes, and none of those wounds was in his back.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا أَحْمَدُ، حَدَّثَنَا ابْنُ وَهْبٍ، عَنْ عَمْرٍو، عَنِ ابْنِ أَبِي هِلاَلٍ، قَالَ وَأَخْبَرَنِي نَافِعٌ، أَنَّ ابْنَ عُمَرَ، أَخْبَرَهُ أَنَّهُ، وَقَفَ عَلَى جَعْفَرٍ يَوْمَئِذٍ وَهْوَ قَتِيلٌ، فَعَدَدْتُ بِهِ خَمْسِينَ بَيْنَ طَعْنَةٍ وَضَرْبَةٍ، لَيْسَ مِنْهَا شَىْءٌ فِي دُبُرِهِ. يَعْنِي فِي ظَهْرِهِ.
sunnah.com