CHICAGO (AP) — An independent autopsy commissioned by the family of Nolan Xavier Wells found the 18-year-old’s cause and manner of death to be “undetermined” pending further investigation.The civil rights attorney Ben Crump, who is representing the Wells family, announced the preliminary findings Wednesday in front of a standing-room-only crowd at the annual NAACP National Convention in Chicago.Reading from a report prepared by forensic pathologist Dr. Robert Mitchell, Crump said the report showed no evidence of fractures or bruising, but also did not rule out the possibility of foul play.The board-certified pathologist found “red discoloration” in the soft tissue in the back of Wells’ head, but no underlying skull fractures or lacerations to the skin around the area, Crump said. He noted that the decomposition of the body, along with other limiting factors, had made it impossible to make a determination.

Without further information, the pathologist wrote he “cannot rule out if any intervening nonaccidental factors contributed to or caused the death of Nolan Wells,” according to the attorney.The autopsy is part of an independent investigation led by Crump into the circumstances of the teenager’s disappearance, which followed a July 4 boat trip with friends to an island off the coast of Mississippi. Wells did not return to the mainland with his friends. His body was found floating off the island’s coast two days later.