'We have not given up': Still no suspects in case of missing Dulce Maria Alavez on 1-month anniversary of disappearance

One month ago, 5-year-old Dulce Maria Alavez was playing with her 3-year-old brother in a New Jersey park. She had been on the swings when she suddenly disappeared.

She has been missing since that day on Sept. 16.

Authorities have conducted multiple searches, scoured the area where Dulce was last seen and processed thousands of tips.

Yet few answers or clues have developed.

"We have not given up and remain hopeful that we will determine the circumstances that led to Dulce’s disappearance," Cumberland County Prosecutor Jennifer Webb-McRae said in a statement on Wednesday, marking the one-month anniversary of her disappearance.

Authorities still have no strong suspects, but on Tuesday a sketch was released of a man they believe is a "possible witness."

The prosecutor's office said the man in the sketch is someone who they want to speak with, but noted they are not identifying him as a suspect or person of interest.

He was allegedly at the park around the time Dulce went missing in the afternoon near City Park in Bridgeton. A witness recently came forward with his description and told authorities that he was seen with one or two children under the age of 5 years old.

It was not immediately clear if one of the children was Dulce, and Webb-McRae told ABC News she could not comment on specifics in the investigation.

Dulce's family has pleaded for anyone with information on her or her disappearance to come forward.

“She’s just an innocent girl. She’s just 5 years old. She doesn’t know nothing of the world that we know,” Noema Alavez Perez, Dulce's mom, said at a Sept. 30 press conference.

Webb-McRae has said that she is working with the hope that Dulce is alive.

Anyone with information on the man or the case is asked to contact Bridgeton Police Department at 856-451-0033 or anonymously text information to TIP411 with the word "Bridgeton."