Nolan Wells' Phone Allegedly Had Messages Deleted After His Final Use

Nolan Wells' cellphone tells a troubling story ... messages were allegedly deleted after he last used the device, and the records contain conversations about "sketchy" people on Horn Island.

Attorney Ben Crump and the family's digital-forensics team laid out the findings at a press conference Thursday ... saying Nolan last used his phone at 2:18 PM on the day he died ... and showing a map of GPS coordinates tracing Nolan's phone from the island to when his parents ultimately retrieved the phone.

Andrew Garrett -- the forensic examiner hired by Nolan's parents -- says messages were deleted between Nolan's last phone activity and the time his family regained access to the device. Garrett says his team cannot determine who deleted the messages or why.

Nolan used Snapchat and Instagram for roughly 95% of his communications ... and Garrett says the examination produced 282 pages of records that mostly consisted of Snapchat data.

He says people in one group chat continued messaging after Nolan's death ... apparently unaware their messages were still syncing to his phone.

Crump says some of the messages they obtained show Nolan's friends discussing whether people on Horn Island could be racist.

One exchange refers to two "really sketchy-looking guys" in boats ... while another recounts a sheriff allegedly warning Nolan's father he "wouldn't want to be left alone with them, especially if they're really drunk."

Crump stressed there is no definitive proof Nolan's death was racially motivated ... but said his parents have never accepted the idea that he simply drowned and nobody saw anything.

Nolan's parents' attorneys also point to discrepancies between the state medical examiner's report and the independent autopsy ... adding to their calls for a closer look at his death.

As TMZ previously reported, an independent autopsy commissioned by Nolan's family found blunt-force trauma to the back of his head and additional injuries to his back.

The cell phone details come after a Mississippi grand jury declined to pursue criminal charges ... saying Nolan's body was found in a position consistent with drowning.

Crump says the investigation should remain open until officials answer how Nolan suffered the injuries and whether they contributed to his death.