The 18-year-old apparently went missing off the coast of Missisippi during a raucous Fourth of July party

NEED TO KNOW

Nolan Wells’ mysterious death is potentially even more unusual: If he drowned on Horn Island, off the coast of Mississippi, that would mark the first such death there in years, government data shows.

The drowning dangers around the barrier island — where the water can deepen rapidly and churn with rip currents like a washing machine — have attracted significant attention since Wells’ body was found there on July 6, still wearing his swim trunks.

Two days earlier, the 18-year-old attended a large, raucous Fourth of July party with friends who say they left him behind with a girl, an account his family has challenged as being out of character for him.

Authorities initially said they suspected that Wells drowned and did not see signs of foul play — a position they have since seemingly softened amid their ongoing work and sharp criticism from the teen’s parents.

“Nolan Wells’ family deserves a thorough and factual investigation, and that’s exactly what they’re going to get,” Jackson County Sheriff John Ledbetter told ABC News.

Despite the currents and deep water around Horn Island, and its history as a popular gathering spot, according to locals, data obtained by PEOPLE indicates that recent drownings there are rare.

The Jackson County coroner said there were no recorded drowning deaths at Horn Island in the last six years, an official tells PEOPLE in response to an open records request.

That doesn’t mean drownings don’t happen in the area. There was a drowning death investigation at nearby Petit Bois Island in the same time period, the official says. And a teenage girl was taken in critical condition to the hospital from Dauphin Island, not far from Horn Island, in 2022 after being stuck in the water.

Wells’ parents, Christine and Elmore Wonsley, and their attorney Ben Crump have questioned what really happened to him on July 4 before he apparently vanished in plain sight and later turned up dead.

More than a month later, much remains unclear about Wells’ final hours alive.

A few other attendees at the party that day have described a big, bustling event with drinking, socializing and occasional altercations.

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Both an official and independent investigation are ongoing, and the Jackson County district attorney has said the findings will be presented to a grand jury.

An independent autopsy on behalf of Wells’ family could not determine his cause of death or rule out foul play. While the examination faced some key limitations, it did not find any severe injuries on his body.

The results of the official autopsy have not been released.

Wells would have turned 19 this week.