Alicia Scheideger, the boy's mother, told ABC News her ex-husband, who is stationed at Fort Bragg in North Carolina, had custody of the boy. She said she was the one who notified authorities of the video, which has been removed from the Internet.

"I was horrified. It's a baby cockfight just like somebody put two animals up to fight each other," Scheideger said.

A male voice can be heard on the tape encouraging the boys, at one point saying, "Go on, hit him back. I don't care."

The boy has been removed from his father's custody and is now with a relative. The Army, in a statement, said it is cooperating with civilian agencies. The second child was not identified but the boys were not related, ABC said.

The Army released a statement about the video, The Fayetteville Observer reported.

"The behavior displayed by the parents in the video is neither condoned nor indicative of soldiers in this command or the Army," the statement said. "The command takes very seriously the health and welfare of all service members and their families. This command will take the appropriate actions as required and will continue to cooperate with civilian agencies."