April 23 (UPI) -- The remains of three young children have been uncovered in a wooded area in Tennessee, Memphis Police Chief Cerelyn Davis announced.

Local authorities were trying to find the causes of death and the identities of the children who were believed to be between ages 3 and 7, Davis said Wednesday. A search of local missing children did not find any matches, she said.

"Somebody knows where these children have come from. Someone knows of missing children that we have discovered in this area," Davis said. "This is heartbreaking, it's disturbing.

"We know that this individual was not, or these individuals were not, persons that were reported out of our area," Davis said.

On March 8, a person walking their dog in the woods near Hickory Hill in southwest Memphis discovered a potential human skull and reported it to police. During the following weeks, investigators from the Memphis Police homicide unit and the Shelby County Medical Examiner's Office worked to find the other remains, some of which were found in a drainage pipe.