The scene is preserved pending a full Garda tecnhincal examination and the body remains at the scene.
Earlier today Gardai had issued a renewed appeal for missing teen Anastasia Kriegel (14).
Anastasia, who was from Leixlip, Co Kildare, had been missing for three days.
Gardaí at Lucan in County Dublin, who are now investigating the disappearance of a 14-year-old girl, have discovered the body of a female.
Gardaí also believe she was not alone in St Catherine's Park, Lucan, when last seen alive.
Gardaí said it was only when the remains had been removed and a full postmortem carried out that the cause of death would be confirmed and the suspicious death inquiry would be upgraded to murder.
"We are at this time treating the death as suspicious".
"They have another child in that house as well so they have to be very careful around that", Supt Gordon added.
One resident, who lives close to St Catherine's Park, spoke of their shock at the news the girl's body had been found.
"We have an incident room set up, we have the technical bureau, Dr Marie Cassidy will be attending the scene, and we are conducting searches as we speak".