OCEAN SPRINGS, Mississippi — New footage circulating online has renewed attention in the death of 18-year-old Nolan Wells, who disappeared during a Fourth of July boat trip to Horn Island.

The footage allegedly shows some of Wells' friends cleaning a boat at a dock around 6:10 p.m. on July 4, hours after returning from Horn Island without him. It has not been independently confirmed that the individuals seen in the footage are Wells' friends.

Wells traveled by boat with friends to Horn Island, Mississippi, for a Fourth of July outing before being reported missing later that night. His body was found near the island two days later on July 6.

According to GPS and dispatch records reviewed by CBS, NBC and Mississippi Department of Marine Resources:

- The boat left its dock shortly before 10 a.m. on July 4 and arrived at Horn Island at 11:14 a.m. - Around 4 p.m., a panicked teen called Sea Tow saying the bilge pump failed and "We're sinking." - GPS shows the boat left Horn Island at 4:31 p.m. and was back at its original dock at 5:44 p.m., then in Fort Bayou at 5:52 p.m. and back at the dock at 6:06 p.m. - At 7:19 p.m. it went to Fort Bayou boat launch before being towed over land to Biloxi.

Wells' friends told authorities he chose to stay behind on the island with a young woman he had met that day rather than ride back with the group. Witnesses told police they spotted someone matching his description on the island as late as 6:00 p.m.

The Mississippi State Medical Examiner listed his cause and manner of death as undetermined, while noting injuries to the back of his head. A grand jury later found insufficient evidence of criminal wrongdoing and said the circumstances were consistent with drowning.

The Wells family commissioned an independent autopsy by Dr. Roger A. Mitchell, which also listed cause and manner as undetermined. The family, represented by civil rights attorney Ben Crump, continues to seek answers surrounding his death.

The official state autopsy was sealed July 31 for grand jury proceedings and remains sealed.

Officials have said foul play is not suspected, but investigators have not publicly confirmed the identities of individuals in the new dock-cleaning video.

NolanWells

Sources: Mississippi Department of Marine Resources, Jackson County Sheriff's Office, ABC News, NBC News, BallerAlert.

18-year-old Nolan Wells who went missing after July 4 boat trip to Horn Island Mississippi
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