When two or more people or groups are in confrontation, it means they are clashing or disputing with each other. There are several synonyms that can be used to describe this situation. One common phrase is "in conflict." This suggests that there is a disagreement or tension between the parties involved. "At odds" is another option, which carries a similar meaning of being in opposition or disagreement. "Facing off" can be used to describe a more confrontational situation, where the parties are positioned directly opposite each other. And finally, "embroiled" implies that the parties are deeply involved in a conflict or dispute with each other.