California detectives again searched the church where Sunday school was taught by the woman accused in the grisly rape and murder of her daughter's 8-year-old friend.

Police on Tuesday also went back to scour the home where Melissa Huckaby, 28, lived a few doors down from little Sandra Cantu, in the town of Tracy.

It was the second time authorities searched Huckaby's home and the Clover Road Baptist Church in Tracy, where her grandfather was the pastor.

The Sunday school teacher was tearfully arraigned Tuesday afternoon on charges she kidnapped the little girl, raped her using a "foreign object" and then killed her.

Sandra disappeared March 27. She was last seen on surveillance camera skipping down the street outside the Orchard Estates Mobile Home Park, where she lived with her family.

The second-grader's body was found in a suitcase at the bottom of a pond on April 6.

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Tracy police Sgt. Tony Sheneman would not say why police returned to the church and home, which were also searched in the days after Sandra's body was found.

But he said police are continuing to investigate Huckaby, who they believe acted alone.

"We have been unable to determine a motive," he told FOX News Wednesday. "She didn't provide one during her interview. It is shocking for a mother to kill another mother's child. It's a statistical anomaly."

He said Huckaby was not on suicide watch in prison, but was under general observation.

"She has not made any statements to lead us to believe she is a danger to herself," Sheneman told FOX.

Huckaby appeared in a San Joaquin County courtroom Tuesday for her arraignment in a red jumpsuit and shackles, trembling and crying as a judge read the charge: one count of murder with the special circumstances of rape with a foreign object, lewd or lascivious conduct with a child under 14 and murder in the course of a kidnapping.

The special circumstances mean Huckaby, if convicted, could face life in prison without the possibility of parole or the death penalty. District Attorney James Willett said Tuesday he has not decided whether to seek the death penalty.

A 10-day search by law enforcement and the community ended on April 6, when farmworkers draining an irrigation pond a few miles away from the mobile home complex found the suitcase containing Sandra's body.

Police have said Sandra was found wearing the same clothes she had on when she was last seen: a pink "Hello Kitty" T-shirt and black leggings. They have not said how, why or where she was killed, and the coroner's office has said autopsy results are pending.

The complaint said the murder happened "on or about" March 27, but gave no other details.

Huckaby was arrested Friday, hours after she told a Tracy Press reporter that the suitcase was hers but it had been stolen the day Sandra vanished.

Huckaby's family has described her as a loving mother who had a strong religious background and wouldn't hurt anyone. She lived with her grandparents.

Relatives visited Huckaby at San Joaquin County Jail on Monday night, where she had been under observation. That was the first time they'd seen her since her arrest.

Huckaby's father, Brian Lawless, said the family cried and prayed together during the visit.

"She's not getting much sleep but in spite of all that that she looks good," he said afterwards. "We're in shock ... The young lady I see on film, that's not my daughter."

A public memorial service is scheduled for Sandra in Tracy on Thursday.

Huckaby has been ordered to return to court on April 24, when she's expected to enter a plea.

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The Associated Press contributed to this report.