The discovery was made in the Carlton Reserve in North Port, in an area that has been under water until recently, CNN says citing FBI Special Agent in Charge Michael McPherson.
The remains appear to have "been there a while," a source told the news outlet.
Laundrie has been a person of interest in the killing of his girlfriend, Gabby Petito. He was charged with fraud for apparently using her debit card after she had died.
Identifying the remains may take some time due to the condition of which they were found. Laundrie had last been seen 37 days ago.
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