An FBI investigation into a missing-person case on the Yavapai-Apache Nation Indian Reservation turned into an investigation of an extremely gruesome murder.

Investigators believe 35-year-old Mario Chagolla Jr., a non-tribal member who lives in Camp Verde, stabbed a Native American man to death before cutting off his head and limbs with a circular saw, pulling the teeth out of his head, and tossing most of the parts in a fire, according to a federal complaint.

Much of this actually happened in front of witnesses, according to the complaint, one of whom told investigators that he and four other guys, Chagolla included, were all drinking and playing cards together on the evening of June 16.

Chagolla, referring to the victim, Dwayne Beauty, told one of the men he was going to "get that mark," but the witnesses didn't know what he meant by that.

At one point that night, Chagolla came up behind Beauty in the kitchen of the house -- which is owned by another man -- and took him to the ground, kicking him several times.

Chagolla was yelling at Beauty about "not messing with a friend's woman" and asked for duct tape -- which someone gave to him. Chagolla taped Beauty's hands behind his back, took a knife out of a drawer in the kitchen, and stabbed him over and over. Beauty wasn't even moving anymore, and Chagolla only stopped stabbing him because the knife broke off in Beauty's head.

A witness said Chagolla came back with the circular, and cut off Beauty's head, hands, and legs, leaving "nothing left but a torso," the complaint states.

Chagolla then held Beauty's head in the air and said something to the effect of, "This is what you get for messing with somebody else's girl," the complaint states.

While at the home, Chagolla extracted the teeth from Beauty's head, and tossed the teeth, as well as Beauty's hands, into a fire.

Chagolla left the house with the rest of the body parts in bags, and came back later saying he burned all of it except the torso, which he said he kept.

Chagolla told a friend not to say anything or he'd kill them and told him, "This is not my first rodeo," according to the complaint.

A detective for the reservation police department found out that the girlfriend of one of the men at the house that night, Kathy Englund, died about three months ago. Although Englund died from alcohol toxicity, Chagolla apparently blamed Beauty for her death.

The same day FBI agents were interviewing people, June 20, Chagolla's father called police to report that he thought he found human remains on his property. Chagolla was staying in his father's trailer the day of the murder, when his father was out of town.

FBI agents arrested Chagolla last week, as Chagolla lost a brief foot race with agents, according to the complaint.

According to a filing from a magistrate judge, Chagolla has not been cooperative, although he did claim he was paid $750 to kill Beauty. His state prison record includes a stay for about a year and a half for trying to run from police.

Perhaps miraculously, federal authorities have not filed complaints against any of the other men at the house that night.

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