Delaware police are trying to identify the remains of a young girl whose body was found near a softball field in September.
Earlier this week, the Smyrna Police Department released facial reconstruction sketches of the child, who they say is likely Caucasian or Hispanic, with slightly wavy brown hair. They say the child is between 2 and 5 years old.
The girl’s remains were discovered around 4:30 p.m. on Sept. 13 by a family near the Little Lass softball fields, across the road from Smyrna Middle School.
“We had a family down there who had a pet and the dog came back with some type of bone,” Smyrna Police Department Corporal Brian Donner tells PEOPLE. “They thought it was suspicious and they called police.”
Police say they are treating the case as a homicide.
“Whoever is accountable for this child’s death, we will hold them responsible,” says Donner.
Investigators believe the child, whose nickname is Baby Elle, had been dead for several weeks or possibly longer before she was found. An anthropological exam of her remains suggest that she suffered from a chronic illness. However, it is unclear how the child died.
“When they were examining her remains they observed some things that would suggest that she suffered from a chronic illness,” Carol Schweitzer, a Forensic Services Unit Supervisor with the National Center for Missing & Exploited Children, tells PEOPLE. “She had been sick for a while.”
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Schweitzer says they won’t know her exact illness until she is identified.
Donner says the case has shaken the community and officers handling the case.
“This is a small, close-knit community. Everyone is intertwined, and stuff like this doesn’t happen every day,” he says. “It is a little bit shocking to the senses when it happens this close to home.”
The National Center for Missing & Exploited Children assists on 700 cases of missing victims under the age of 21 across the country. Some of the cases go back several decades, Schweitzer says.
Schweitzer says she is optimistic that the identity of Baby Elle will be learned.
“We know sometimes it takes a while to circulate the images but we are really hoping the right person will see this,” she says. “It just takes that one person to connect the dots.”
There was some speculation that Baby Elle was Dulce Maria Alavez, a young girl who went missing from a Cumberland County park in Bridgeton, New Jersey. But police say the two cases are not connected and that Dulce vanished days after Baby Elle’s remains were recovered.
Donner says hundreds of tips have poured in since they have released the sketches — but 70 percent have been about Dulce.
Schweitzer says that there is a good chance Baby Elle might not be of school age yet.
“We are hoping people will think of a child in their neighborhood or a daycare situation where they haven’t seen a little girl in a while,” she says.
Anyone with information about Baby Elle is asked to contact Smyrna Police Detective Bill Davis at 302-653-3490, reach out to the department on Facebook or Twitter, call Crime Stoppers at 1-800-TIP-3333, or call the National Center for Missing or Exploited Children at 1-800-THE-LOST.