New York (CNN) -- After 22 years on a cold case, the New York Police Department finally has a lead.
The NYPD was able to identify the mother of "Baby Hope," a little girl whose body was found in a blue and white picnic cooler in a wooded area near the Henry Hudson Parkway on July 23, 1991.
The girl, then believed to be 3 to 5 years old, was smothered and sexually molested. Her body was so badly decomposed that several sketches were made to suggest what she looked like.
Thanks to a tip, the department has confirmed the identity of the girl's mother through DNA testing, according to Police Commissioner Ray Kelly. The body was exhumed in 2011.
"A DNA match was made with the mother and the mother has been cooperating," Kelly told reporters Tuesday. He declined to name the mother or provide details on the case.
There have been no arrests.
"Homicide is a distinct possibility here, so it's going to go forward in that direction," Kelly said of the investigation.
Baby Hope -- named by the police officers and detectives moved by her unknown story -- finally has a name and an age. The NYPD, however, is not ready to release this information so as to not disturb the ongoing investigation.
The girl was never reported missing and police could not track down anyone who might have known her.
The NYPD Cold Case Apprehension Squad never gave up hope, continuing to hand out flyers and canvas nearby neighborhoods every year on the anniversary of the discovery of the body.
"We have been able to identify the mother of Baby Hope as a result of, in my judgment, outstanding detective work," Kelly said.
Detective Robert Dewhurst, a member of the squad, told CNN in July that several detectives were still on the case and that people with information may speak many years later for many reasons, such as feeling safer after moving to a new area where they don't see the person responsible every day.
Sometimes people "want to get it off their chest," said Dewhurst.
For months after Baby Hope's body was found, police went back to the site hoping whoever was responsible, driven by guilt, had left some type of memorial that would have helped police.
Baby Hope, two years after she was found, was laid to rest in a donated plot. She was buried in a white dress bought by a detective's wife.
"This is what my squad does," Dewhurst said. "Twenty years is not uncommon for a cold case."
"I have hope. Otherwise I wouldn't be doing this."