Nolan Wells’ family called for a federal investigation into his death on Monday after a grand jury reviewing the evidence determined last month that no criminal charges are warranted in this case.

The 18-year-old’s body was recovered on July 6, and authorities at the time said they suspect he drowned, but a grand jury was convened to review the evidence. The grand jury of 23 people found “no credible evidence to support the public allegations” that anyone riding to or from the island that day surrounding Wells “engaged in any criminal conduct related to” his death, according to the report released on Sept. 21. The report says that the “position of, condition of, time of discovery, and location” of Wells’ body off the coast of Mississippi this July is “consistent with drowning.”

The private autopsy commissioned by Wells’ family and the official state autopsy both found Wells’ cause and manner of death to be “undetermined.” Wells’ parents were joined at a press conference on Monday afternoon by their attorney Ben Crump and Cynthia Choi, executive director of Stop AAPI Hate, as Wells was Black and Filipino American. They called on the Federal Bureau of Investigation and the U.S. Department of Justice to launch an investigation into the teen’s death. Crump also shared a letter from Florida Rep. Frederica Wilson, calling on the National Park Service to investigate his death on Horn Island, which is overseen by NPS. The circumstances surrounding Wells’ death garnered national interest after the college football player went missing on the 4th of July after going on a boat trip with friends to Horn Island. Officials said it appeared Wells stayed behind on the island after his friends left. The state autopsy report indicated that the pathologist found “evidence of injury” to the back on Wells’ head that is described as “two dark red-purple subcutaneous scalp contusions.”

The grand jury reviewed the findings of the private and the state autopsies as part of the evidence in this case, Jackson County District Attorney Angel Myers McIlrath — who convened the group — said in a Sept. 24 statement.