Gardaí believe bones found next to an old Cork railway line, wrapped in cloth with a small piece of religious jewellery are female and more recent than initially suspected.
Detectives are now awaiting the results of pathology and forensic anthropology tests to determine if the remains are female rather than male.
They also want to find out if the remains date to a time period over the last five to 25 years.
It was initially suspected the remains were historic, dating back to the early 20th Century and those of an adult male, possibly linked to the War of Independence.
A painstaking excavation of the site at Roxborough off the old Midleton-Youghal rail line has yielded multiple bones, with a skull initially discovered on Tuesday evening by workmen converting the railway into a new €19.8m greenway.
The discovery of further bones, yielding almost a complete skeleton, has now led gardaí to suspect they are dealing with the remains of a woman and a more recent death.
One garda source indicated that "significant" material was also found in the area excavated. This included a quantity of disintegrated clothing and possible personal items of the deceased.
Most intriguing was a small religious token or piece of jewellery found with the remains.
The bones have now been removed to Cork University Hospital (CUH) for examination by assistant State pathologist Dr Margaret Bolster and a forensic anthropologist.
Tests will now be conducted to determine if all the bones are from the same individual.
A full list of missing persons from the greater east Cork area over the past 50 years is currently being compiled.
Among the highest profile missing person cases locally is that of Tina Satchwell, who was 45 when she vanished without trace from her home in Youghal on March 20, 2017.
A major garda search operation failed to reveal any trace of Ms Satchwell's whereabouts.
Gardaí said they are now awaiting the results of expert tests which will include carbon dating and DNA sampling.
One source said they were hopeful of identifying the remains given the condition of the bones, skull and teeth.
"Gardaí are continuing to investigate the discovery of suspected skeletal remains found in Roxborough near Midleton, Co Cork at approximately 4.30pm on Tuesday," a spokesperson said.
"The area remains sealed off as gardaí continue to carry out a technical examination. The State pathologist has attended. The outcome of these examinations will determine the course of the investigation."