The FBI has joined in on the search for a 5-year-old girl believed to have been abducted from a park in Cumberland County.

Dulce Maria Alavez has been missing since Monday afternoon. Authorities say that she was at the City Park Playground in Bridgeton with her younger brother. Her mother was in the car nearby with an 8-year-old relative.

Police say that the younger brother came back to the car without his sister. She was nowhere to be found.

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On Tuesday, police issued an Amber Alert and say that they believe that the young girl was abducted. Authorities say that Alavez was spotted Monday afternoon in the back of a red van with a sliding side door and tinted windows. They believe that she was in the company of a light-skinned, possibly Hispanic man with acne on his face. Police say that they do not have a license plate number.

Police were back at the park Wednesday looking at surveillance video and visiting the areas of the park that they believe Alavez was on Monday.

They say that they hope that anyone who was at the park on Monday contacts them so that they can ask them some questions about what they may have seen. Police say that they will interview as many people as they can and that they are looking at all leads – including family members.

"Sometimes tough questions have to be asked in an interview and people take offense to that because they feel you're implicating a family member or significant other, but they're just questions we have to clear up,” says Bridgeton Police Chief Michael Gaimari.

The car that belongs to Alavez’s mother was towed from the park Tuesday for the investigation.

The girl’s family was at the park Wednesday morning asking for and praying for her return.

“She means a lot to me. I would give anything for her to come back,” says Nayiber Alavez, the girl’s aunt.

Police say that Alavez was last seen wearing a yellow shirt and black-and-white checkered pants.

The man she was allegedly spotted with was wearing orange sneakers, red pants and a black shirt.

Authorities add that Alavez's father lives in Mexico and is not a factor in the investigation.

Anyone who may have information about the girl's whereabouts is asked to call Bridgeton police at 856-451-0033. Information can be sent anonymously by texting "Bridgeton" to TIP411.