In the immediate aftermath of the shooting, the Border Patrol and other federal and local agencies flooded the area with personnel looking for who they believed were assailants who had attacked the agents.
"That was the initial reports from the beginning," McCubbin said. "That was the reason for the saturation manhunt there. They even had permission to fly into Mexico. They were seeking people out. What this was based on, we'd have to assume it was based on the initial statements given by the agents on the scene."
Two people suspected of being involved in the shooting were arrested by the Mexican government but were apparently not involved at all.
"They had a couple of people in custody but other than being in the area, there was no evidence putting them there at the scene," McCubbin said. "They could have been guides, they could have been scouts, and those type of folks typically go back and forth all the time anyway."
Rothrock said he believed the agents' actions were "appropriate and in accordance with their training had they, in fact, been engaging people involved in illegal activities. Unfortunately, they weren't engaging people involved in illegal activities, they were engaging each other."
Rothrock said he doubted any legal action will be taken against the surviving agents.
Ivie's funeral is set for Monday morning Sierra Vista, Ariz..
"It's happened and it's a horrible tragedy for the agents involved and their families and the agency," McCubbin said. "We can come up with some reasons as to how this happened but that doesn't fix anything. All we can do is send prayers to the families and all the agents involved that somehow they can find some peace with this someday."
Ivie's death marked the first fatal shooting of an agent since a deadly 2010 firefight with Mexican gunmen that killed U.S. Border Patrol Agent Brian Terry in December 2010 and spawned congressional probes of a botched government gun-smuggling investigation.