Alma 24
If more people joined the people of Anti-Nephi-Lehi than were killed in the attack by the other Lamanites then we know that some who joined had not committed a murder first. Once we consider than none of the Amulonites or Amalakites joined, and that they did most of the killing, we can realize that few, if any, of those who killed their defenseless enemies converted that day. I think that the former Nephites stopped their killing because they saw that they were losing their influence over the Lamanites who had not been converted by the teaching of the sons of Mosiah.