"I heard the Messenger of Allah [SAW] say: 'If two Muslims confront each other with their swords and one of them kills the other, both the killer and the slain will be in Hell.'" They said: "O Messenger of Allah, (we understand about) the killer, but what about the one who is killed?" He said: "He wanted to kill his companion." (Using translation from Nasāʾī 4122)
أَنَّ رَسُولَ اللهِ ﷺ قَالَ «إِذَا تَوَاجَهَ الْمُسْلِمَانِ بِسَيْفَيْهِمَا فَقَتَلَ أَحَدُهُمَا صَاحِبَهُ فَالْقَاتِلُ وَالْمَقْتُولُ فِي النَّارِ» قَالَ رَجُلٌ يَا رَسُولَ اللهِ هَذَا الْقَاتِلُ فَمَا بَالُ الْمَقْتُولِ؟ قَالَ «إِنَّهُ أَرَادَ قَتْلَ صَاحِبِهِ»