JACKSONVILLE, Fla. — A day after human bones were found at a highway construction site in Jacksonville's Oceanway neighborhood Tuesday, a forensic investigator told First Coast News that investigators have a painstaking process of searching for more evidence.

"It starts with finding as many bones as possible because you need to identify the victim first," Michael LaForte said in an interview at his office Tuesday.

LaForte, retired from a 30-year career with the Jacksonville Sheriff's Office during which he processed hundreds of homicide scenes, looked at a photo taken of a skull and a possible leg bone at the discovery location.

"It’s obvious the body’s been deceased for quite some time," he said. "There’s no tissue, very little tissue left at all on the skull."

But asked for a more precise estimate, LaForte declined to speculate, saying there are myriad factors to consider, including attributes of the surrounding soil, temperatures and more.

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"The environment is the big one," he said. "Once you’re dead, if you’re out in the environment, the elements – especially bugs – can do a fast job, especially in Florida."

Another consideration is that the bones were found in dirt being used to reinforce a retaining wall at the I-295/North Main Street interchange, that had been excavated at a site nearly three miles away, off Eastport Road, where a retention pond is being built.

"Where the bones came from originally, that could be the primary scene," LaForte said, then reminded that there could conceivably be more locations.

"But that could be a secondary scene to a primary scene that they haven’t even found yet," he said, "and then you’ve got where these bones were discovered – that’s the third scene."

LaForte also was reluctant to muse about any connection to any particular cold case -- old or relatively new.

"Everything’s on the table until you rule it out," he admonished. "You have to rule it all out."

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But he did appear confident that the find can lead to answers, eventually.

"Once they can identify who the bones are, that gives them more avenues to go down and hopefully find it to a conclusion," LaForte said, noting that even if DNA from the bones cannot be matched to any profiles in police databases, it can still lead to identification. First, though, such specifics as gender, race, height and age -- all of which can be ascertained or at least estimated by what the skeletal remains reveal -- would be necessary to narrow the list of possible identities.

"They could go to the family and get D.N.A. from the family members – the mother, the father – and then run that against – even if they’re not in the database – compare that with the family members," he said.

LaForte also pointed out that certain bones might also be marked by wounds that indicate the cause of death. Given that only a few bones were found in the initial discovery Tuesday, he said finding as many more as possible is crucial.

"The big job is going to be the excavation," he said. "It could take several days, I would think, to maybe even a week."