King James Version
For the children of Ammon and Moab stood up against the inhabitants of mount Seir, utterly to slay and destroy them: and when they had made an end of the inhabitants of Seir, every one helped to destroy another.English Standard Version
For the men of Ammon and Moab rose against the inhabitants of Mount Seir, devoting them to destruction, and when they had made an end of the inhabitants of Seir, they all helped to destroy one another.New International Version
The men of Ammon and Moab rose up against the men from Mount Seir to destroy and annihilate them. After they finished slaughtering the men from Seir, they helped to destroy one another.