PONTE VEDRA BEACH, Fla. -

Burned remains were discovered in Guana River State Park in South Ponte Vedra on Wednesday, and the remains are believed to be human, according to the St. Johns County Sheriff's Office.

Workers with the Florida Fish and Wildlife Conservation Commission found the remains on the east side of State Road A1A during a scheduled control burn.

Deputies said the origin of the remains is undetermined but they had been there for an extended period of time. They said the Medical Examiner will determine if they are indeed human.

"We'll continue with our investigation and work in coordination with the Medical Examiner's Office to look at evidence, forensic evidence if you will, partially to look at what evidence is there to help ID the victim, if it is in fact a human body," said Sergeant Catherine Payne with the St. Johns County Sheriff's Office.

Sgt. Payne said the autopsy could take days or even weeks.

"It looks like the remains had been there an extended amount of time. They're going to take their time in this investigation to make sure they review everything thoroughly," said Sgt. Payne.

Sgt. Payne said from time to time the Florida Wildlife Conservation and Department of Forestry will conduct controlled burns in that area. She said it's not out of the ordinary to find remains, but most of the time they're not human remains.

"It's too early to determine whether foul play is suspected. The remains look like they've been there an extended amount of time. So robbery homicide detectives have quite the challenge in front of them to find the identity of the victim, or the remains I should say," said Sgt. Payne.

Detectives were on scene investigating and stopped at 6:30 p.m. because of darkness. They will continue the investigation Thursday.

They said it was too early to determine if the remains were connected to any missing person cases.