TRACY, Calif. — Police and residents of this northern California town were shocked when the suspect in the killing of an 8-year-old girl found stuffed into a suitcase turned out to be a woman, the mother of the slain girl's best friend.
The motive in the killing had not been determined.
Melissa Huckaby, a Sunday school teacher and granddaughter of a minister, was on suicide watch at the San Joaquin County Jail, where she remained in custody Sunday without bail on suspicion of kidnapping and killing Sandra Cantu.
Sandra's body was found in Huckaby's suitcase in an irrigation pond nearly a week ago, police said.
"This was an anomaly in the murder of a child," police Sgt. Tony Sheneman said at a news conference Saturday in this northern California town. "Finding out that it is a woman who is responsible for Sandra's kidnapping and murder, and then finding out it is a member of the community is another blow."
Killings by women unusual
FBI statistics show women are involved in just 7 percent of murders of any sort. Solo killings of children by women are even more unusual.
"It's very unusual for women to be involved in an abduction and murder of a child," said Candice DeLong, a retired FBI profiler based in San Francisco. "Sometimes we see this when the woman is working with a male partner. It does not appear to be the case this time. But this was not a sexually motivated crime."
Sandra disappeared on March 27 and hundreds of volunteers and law enforcement officials turned out to search for her. Pictures of the girl with dark brown eyes and light brown hair were posted all over Tracy, a city of 78,000 people about 60 miles (100 kilometers) east of San Francisco. Police said they received 1,500 tips.
Huckaby, 28, had attended the second of several vigils for the slain girl, Sheneman said.
Police would not say where or how the girl was killed, though investigators said they believed she died very soon after she was last seen.
Autopsy results are not yet available, and investigators declined to say whether they believe the slaying was accidental or deliberate.
Inconsistencies in Huckaby's story led to her arrest, Sheneman said. There are no other suspects and no other arrests are expected, he said. Her arraignment is scheduled for Tuesday.
Completely out of character
Several of Huckaby's relatives appeared briefly before reporters Sunday. One man, who would only describe himself as a member of the family, read a statement saying the allegations against Huckaby were completely out of character.
The man was joined by several other relatives, including Huckaby's grandfather, Clifford Lawless, who is pastor of the nearby Clover Road Baptist Church, which was searched by authorities after Cantu's body was discovered.
Huckaby taught Sunday school at the church and lived with Lawless in the Orchard Estates Mobile Home Park that also was Sandra's home.
Huckaby's uncle, John Hughes Jr. of Whittier, told The Associated Press his niece was from a good home, but had hit a rough patch in her life and had moved in with her grandparents in Tracy to get past her troubles.
"They opened their home up to her to try to get her life back on track. I think a lot of families have problems like that," Hughes said.
Video: Sunday school teacher held in girl’s death Huckaby grew up in Orange County and was a "pretty normal kid," he said. As the eldest of nine grandchildren, she played "mother hen" to the younger children when the family got together for the holidays.
Rocky path after graduation
After graduating from high school, Huckaby's path appears to have become rockier. She married, had a daughter and was divorced in a few short years. She had difficulty finding and keeping a job, partly owing to the challenges of single motherhood, Hughes said.
"She's had her struggles," he said. "But there's no way (her grandparents) or anybody would be fearful that anything this horrifying could possibly come from that."
Huckaby had been scheduled to appear in court on April 17 to check in with a county mental health program as part of a three-year probation sentence for a petty theft charge to which she pleaded no contest.
She was arrested late Friday, about five hours after she drove herself to the local police station at the request of officers.
"She was calm, cool and collected, then she became very emotional," Sheneman said.
It was not immediately clear if Huckaby had hired an attorney to speak for her.
NBC News and The Associated Press contributed to this report.