“误向自己人开火”可以翻译为 "mistakenly fire on one's own side" 或 "accidentally open fire on one's own troops/comrades"。
"mistakenly fire on one's own side" 强调“误”和“向自己人开火”的动作，较为简洁直接。
"accidentally open fire on one's own troops/comrades" 则更具体地指出了是“向自己的部队/战友开火”，同时“accidentally”也表达了“误”的意思，适合在更具体的语境中使用。