明火执仗：形容公开抢劫或肆无忌惮地做坏事
Carry torches and weapons (clubs) in a robbery -- conduct evil activities openly; a daring robbery; commit armed robbery openly; an armed attack with torches; do evil things openly; fight openly; in an open way; operate in broad daylight
e.g. 隐藏在我们队伍中的敌人当然要比明火执仗的敌人更加危险。
The enemy hidden in our ranks are of course much more dangerous than those acting in broad daylight.
