Where is 8-year-old Sandra Cantu?

The mother of an 8-year-old girl who has been missing from her Northern California home since Friday said she believes her child was abducted.

“I think she was taken, because she would not leave the mobile home park without me — without calling me,” an emotional Maria Chavez told TODAY’s Meredith Vieira Monday.

Chavez’s daughter, Sandra Cantu, came home after school around 3 on Friday afternoon. She went to a friend’s house to play for about an hour before saying she was going back home. She hasn’t been seen since.

“It is our belief that she is alive and unharmed,” said Sgt. Tony Sheneman of the Tracy, Calif., police, who are coordinating a search for the girl with the FBI. More than 200 volunteers combed the trailer park and surrounding area over the weekend, and the search for the girl is ongoing.

‘Full of smiles’
Sheneman joined Chavez and family spokesperson Lisa Encarnacion in a remote hookup from Tracy to update Vieira on the case. He confirmed local reports that four homes in the tight-knit, 100-unit Orchard Estates Mobile Home Park have been searched by law enforcement authorities along with two other locations outside the park. He said that registered sex offenders in the surrounding area have also been interviewed.

“Until we have evidence that an abduction has occurred, we’ll handle this as a missing person,” Sheneman said.

Sandra was described as a happy and outgoing girl with light brown hair and brown eyes. She is 4 feet tall and weighs 45 pounds. She was last seen wearing a Hello Kitty T-shirt, striped dress and black leggings.

“She’s full of smiles. She’s smiling all the time — happy, outgoing. She loves to be outside,” said Chavez, who looked exhausted and fought back tears during the interview.

Encarnacion told Vieira that despite her outgoing nature, Sandra would not have voluntarily left the park with someone she doesn’t know.

“We don’t believe that she would go on her own accord with a stranger,” Encarnacion told Vieira.

Abductee or runaway?
In an earlier interview with NBC-TV Bay Area News, Encarnacion said that she does not agree with police who say that they are not convinced Sandra was abducted. Encarnacion said relatives insist the girl was taken from the mobile home park and did not run away.

“They think that she has just been abducted,” Encarnacion told NBC. “And I know that the law enforcement is reluctant to say that at this moment because there is no concrete evidence to back that up.”

Chavez shares her home with her parents and three other children: Miranda, 11, Tommy, 15, and Simone, 20. Chavez is separated from Sandra’s father, Daniel Cantu, who came north from his Southern California home after Sandra went missing to plead for his daughter’s return.

“Please, bring her home,” Daniel Cantu said during a candlelight vigil held Sunday. “I love you, honey. Please come home soon.”

Video: Police follow new leads in missing girl case The mobile home park has been described as a community in which everyone knows everyone else. Access to the park is limited, with one road leading into and out of the development.

Chavez’s father had recently installed surveillance cameras on the home. One of them captured the last image of Sandra walking away from the home around 4 Friday afternoon, four hours before her worried mother reported her missing.

Vieira asked Chavez if her father installed the cameras because he was concerned about safety in the community.

Chavez indicated safety wasn’t an issue. “It’s been pretty safe over there,” she said before adding, “I thought.”

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