ambushes
n．伏击（复数）：在隐蔽的地方等待，突然袭击敌人的战术。
v．伏击（第三人称单数现在时）：在隐蔽的地方等待，突然袭击敌人。
例句
Three civilians were killed in guerrilla ambushes.
3名平民在游击队的伏击中丧生。
《柯林斯英汉双解大词典》
But preventing ambushes is difficult.
然而要阻止这种“伏击”是困难的。
But ambushes of convoys of security men are certainly taking place.
但是伏击安全人员车队的行动肯定是一直在进行的。
