Sunan an Nasai
4118
Sahih+2

It was narrated from Abu Musa that:The Prophet [SAW] said: "If two Muslims confront each other with swords, and one kills the other, they will both be in Hell." It was 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

SahihAbu Ghuddah
SahihAl-Albani