internecine

详细解释:a. 互相残杀的, 两败俱伤的, 致命的
【法】 互相残杀的, 两败俱伤的, * 的

英语解释：

形容词 internecine:

(of conflict) within a group or organizationcharacterized by bloodshed and carnage for both sides同义词：mutually ruinous