The little girl, then 5 years old, was last seen playing with her younger brother at Bridgeton City Park in Cumberland County on the afternoon of September 16, 2019.
[Ads /]
In the years since she vanished, investigators released age-progression photos showing what Dulce may look like.
About one month after she disappeared, authorities released a sketch of a man who remains a person of interest.
READ MORE: Sketch released of possible witness in case of Dulce Maria Alavez
Action News spoke with family and investigators as they mark the anniversary of Dulce's disappearance.
"I just can't believe it's been three years since Dulce has disappeared. When I thought the FBI was going to be involved I thought she was going to be here fast, but no," said her mother, Noema Alavez Perez.
[Ads /]
Bridgeton Police Chief Michael Gaimari says tips still sporadically come in, and the investigation is still very active.
Authorities have traveled to or communicated with law enforcement in 11 states and Mexico, where Dulce has relatives.
He says the effort has been exhaustive, but there still may be witnesses out there with information.
"There's various video around the park that we were able to analyze, but there are holes in that video where a vehicle might have come in or left and we didn't catch it," said Gaimari.
The chief says even after three years, no one has been ruled out as a person of interest.
On the day of her disappearance, Dulce's mother let the children run off to play on the swings at the playground.
Alavez-Perez and her younger sister stayed inside her vehicle while the children played.
[Ads /]
She would later find her younger son crying, and Dulce was nowhere to be seen.
READ MORE: Mother of missing NJ girl Dulce Marie Alavez tells Dr. Phil she suspects 'old friend' took her daughter
Mother of missing NJ girl speaks to Dr. Phil
Anyone with information is asked to contact the Cumberland County Prosecutor's Office through this form at CCPO.TIPS.
"Information may be left anonymously. We want the public to know that if they are a witness in this matter, their immigration status will not in any way be used against them," the prosecutor's office said.
READ MORE: 'I can't find my daughter': 911 call released in search for Dulce Maria Alavez
911 call released in search for Dulce Maria Alavez