Parents of Nolan Wells call for 'thorough' investigation about his mysterious death

The parents of Nolan Xavier Wells, the 18-year-old student-athlete whose body was recovered on July 6 after a Fourth of July boating trip, called for a transparent investigation as they seek answers about the mysterious death of their son.

Christine and Elmore Wonsley told "Good Morning America" anchor Michael Strahan in an interview on Friday that they have called for a "thorough" investigation as they seek answers about their son's mysterious death.

"We just want honesty and transparency. We want a thorough investigation," Christine Wonsley said. "We want that same respect that would be given to anybody else, and that's it. We just want answers."

Wells, who played football at Southwest Mississippi Community College, went missing during a Fourth of July celebration with high school friends on Horn Island, a popular undeveloped island just south of Ocean Springs, Mississippi, officials said. A body believed to be Wells was recovered on Monday. According to Jackson County Sheriff John Ledbetter, a friend of Wells contacted the Coast Guard around 11 p.m. on July 4. Separately, Wells' mother contacted the sheriff's office about her son around midnight leading into July 5.

The Wonsleys cast doubt on claims by friends that Wells decided to stay behind on the island, while his friends left.

"That we cannot answer," Christine Wonsley said when asked why Wells would stay behind, "I just, I can't -- I can't fathom why he would."

"We always told him, if you go with a group, you stay with a group," Elmore Wonsley said.

Ledbetter told ABC News in an interview that aired on "GMA" on Friday that nothing "yet" from the evidence they collected indicates that foul play was involved in Wells' death, but the investigation will take time and is ongoing, he added.

"We're working towards the same goal as the family. We want a thorough investigation. We're trying to find out everything ," he said. "We are providing a thorough, professional, and accurate investigation. That's what we're going to continue to do, until we arrive at the answers that the family deserves."

"This is a very difficult time for our community. This is a very difficult time for Nolan's family," he added. "Our main objective and our priority is to produce an accurate and professional and very thorough investigation into the death of Nolan, for the sake of his family and for the sake of the community."

The sheriff urged the public for "patience" as investigators look into a "substantial amount" of tips and review photo and video evidence.

"Jackson County is a community that supports its people," he said. "Our community is there for the family."

Christine Wonsley told "GMA" that his family tracked his phone on the Life360 application, but when she went to pick it up from friends, she found that some texts and messages had been deleted, particularly pointing to his Snapchat account.

"When we finally got his phone, me and my sister went through the phone. We went in his Snapchat. He had two accounts. Absolutely nothing," Christine Wonsley said. "It wasn't even 24 hours, which is how long videos and pictures stay in Snapchat ... even my sister was like, yeah, that's suspicious."

"No young person leaves their cell phone," civil rights attorney Ben Crump, who represents the family, told "GMA." "It's not adding up, and that is the problem when you think about the history of Mississippi. Yeah, so there are so many questions that need to be answered."

Crump told ABC News Live Prime anchor Linsey Davis in an interview on Wednesday that the family will "not allow" investigators to "sweep" their son's death "under a rug."

"You're trying to tell us just accept this an accident and sweep it under the rug," Crump said. "His mother, Christine, his father, Elmore, say, no, they will not allow that to happen."

According to Crump, while authorities have told the family that they "don't see any evidence of any foul play," Wells' parents have questions after learning more details about what allegedly took place before their son's disappearance and are calling for a transparent investigation.

Crump said the family is aware of an "altercation" that was "recorded" by students who were on the boat, where "Nolan and somebody" were "yelling at one another."

Crump also said that Wells' friends took his phone with them when they left Horn Island and when his family got his phone back, some messages had been deleted.

"That's something that's really troubling to his family," Crump said.

Asked if Wells could swim, Crump said his father described the 18-year-old college football player as "an elite athlete."

"He said that his son could swim. And so, they're just not accepting that Nolan drowned accidentally," Crump said.

As the family searches for answers, they will conduct an independent autopsy in Washington, D.C., Crump said.

The sheriff's department stressed Wednesday that the investigation is ongoing and urged anyone who was on or near the northwest tip of Horn Island to come forward with photos or videos, "particularly those depicting alleged altercations or containing images of, or believed to include Nolan Wells."

The sheriff's department said it's also looking for anyone who may have seen Wells or "observed or heard an argument, disturbance, or other unusual activity while on the island."

"Even information that may seem insignificant could prove valuable to investigators. We encourage anyone with firsthand knowledge to come forward," the department said.

"Our thoughts, prayers, and condolences remain with Nolan Wells' family during this difficult time," the department added.

ABC News' Sasha Pezenick, Kirk Cohall and Mark Guarino contributed to this report.