India, July 29 -- Newly released video appears to show 18-year-old Nolan Wells was not on his friends' boat when it was being towed away from Mississippi's Horn Island on July 4, adding another development to the ongoing investigation into his death.

New video and photos show Nolan's friends on the boat, getting ready to be towed back to the mainland without him. Seven people can be seen on board but Nolan is not seen anywhere in the footage, which was obtained by "The Officer Tatum Show."

The new footage seemingly confirms what TMZ reported earlier, that authorities have evidence showing Nolan was on Horn Island after the boat left on July 4.

Nolan's friends had called a private towing service after their boat started taking on water ...