MIAMI – Police are said to be investigating a video that allegedly shows a heated argument before Mississippi teen Nolan Xavier Wells went missing and was later found dead – as his grandfather said: “There’s nothing right about this.”

The 18-year-old star football player vanished during a Fourth of July boat trip with friends Saturday and a body which authorities said matched his description was found Monday morning.

Wells was last seen around 3 p.m. Saturday “talking to a girl” at the north end of Horn Island, a popular barrier island about 10 miles off the Mississippi Gulf Coast, the Cajun Navy Jackson County Sheriff’s Department said.

Law enforcement have been looking into a viral clip circulated online which appears to show several people having an “intense” argument near the shoreline, TMZ reported.

It sparked speculation that the tense moment could be connected to Wells’ disappearance.

However, authorities have not confirmed that the footage is authentic or whether the people seen in it have any connection to the college student.

Jackson County Sheriff John Ledbetter said that Wells’ friends had left the island and gone back without him, ABC News reported.

“From what we understand, he chose to stay there,” Ledbetter added.

Ledbetter said in a statement released Tuesday afternoon that officers want to speak with anyone who “observed or heard an argument, disturbance, or other unusual activity while on the island that day.”

Meanwhile, the family of the teen – who played as a wide receiver at Southwest Mississippi Community College – said they were seeking answers.

“Too many unanswered questions — how can a Island that was searched yesterday produce my grandsons body this morning,” his grandfather Christopher Wells Sr. wrote on Facebook on Monday.

“There’s nothing right about this, Nolan Xavier Wells deserved the same things that people he knew and associated with will enjoy in life.”

Wells Sr. later said Wells’ mom Christine and dad Elmore had “prayed for a positive outcome but they also had to prepare themselves for the worst”, adding that “it’s time for answers.”

Photos of the 6-foot-1, 180-pound teen showed him shirtless while sporting blue swim trunks, sunglasses and grinning alongside friends on a boat before he went missing.

The United Cajun Navy non-profit disaster relief organization launched aerial reconnaissance during the search to scour the waters between Horn Island and Ship Island, stretching south to the Chandelier Islands.

The United States Coast Guard, the Mississippi Department of Marine Resources, and the Harrison County Sheriff’s Department also reportedly assisted in the frantic search.