Detectives trying to unravel a murder mystery that left a little girl dead in a suitcase at the bottom of a pond said they haven't yet found the weapon used to kill the 8-year-old and can't say for sure where the luggage came from.

Tracy Police Sgt. Tony Sheneman told reporters Wednesday that investigators haven't recovered the instrument used to murder Sandra Cantu, but said her death is being classified as a homicide.

Sheneman also wouldn't confirm reports that the suitcase her body was found stuffed inside was stolen from the Clover Road Baptist Church, which the FBI searched Tuesday night.

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"I've heard speculation that the suitcase was stolen from the mobile home park (where Sandra lived). I've heard speculation that the suitcase was stolen by the church ... I've heard speculation that it was part of a rummage sale the church was having," Sheneman said. "We did not have a report of stolen luggage."

There were no plans for further searches on Wednesday, he told the news conference. The autopsy that began Tuesday is still under way.

"We’re waiting to hear from the coroner’s office, as I said yesterday. They are working diligently to uncover as much as they can," the sergeant said. "When they complete the investigation, they’ll let us know."

Investigators still refuse to call anyone a suspect in the case.

"We are focusing on no specific person at this time," Sheneman said.

Tracy police will hold their usual evening press conference at 6:30 p.m. EDT (3:30 p.m. PDT).

Earlier Wednesday, the FBI dusted an SUV for fingerprints a day after they searched a church and questioned its pastor for clues to Sandra's suspicious death.

Sandra's body was found in the suitcase, described as "a large rolling piece of luggage" by Sheneman. It had been dumped in a pond near her mobile home in Tracy, Calif., more than a week after she vanished.

She was last seen walking away from her family's trailer park on March 27.

Investigators searched the Clover Road Baptist Church in Tracy well into the night on Tuesday, but wouldn't say what led them to the church or what, if anything, they found there.

They also interviewed Pastor Lane Lawless for three hours, though police insisted he wasn't considered a suspect.

"I just spent a night down at the police station, answering all their questions," Lawless said, according to FOX San Francisco affiliate KTVU.

A night earlier, the TV station reported seeing the pastor's wife, Connie Lawless, being taken away in a patrol car for questioning.

The Lawless family lived in the same trailer park where Sandra resided with her family.

Lane Lawless told KTVU that the second-grader often visited his home and played with their great granddaughter.

Detectives searched the Lawless home Monday night after Sandra's body was identified, and their computers and phones were seized, according to his wife.

"We're very open to them taking anything they wanted," Connie Lawless told KTVU. "We are not at all disturbed by that. We feel that the more people they can eliminate, the quicker they'll get to the truth."

Connie Lawless said they had nothing to do with the girl's abduction.

"She was the sweetest little thing. It breaks it our hearts to think that anyone would take such a tiny little thing and abuse her and murder her," she said.

Investigators won't comment on whether they've been able to link the suitcase Sandra's body was discovered in to any of the locations they've served search warrants on.

"The coroner is taking his time in this painstaking process," Sheneman said Tuesday. "We're not going to ask for him to hurry so as not to damage the integrity of this investigation."

The luggage containing Sandra's body was discovered Monday by farmworkers draining the pond about two miles from where she lived.

The child was wearing the same clothes she wore when she vanished: a pink "Hello Kitty" T-shirt and black leggings.

Investigators believe that the person who dumped the body in the pond must have known the rural area, just north of the city.

"Someone would have to be familiar with that area to know to go there to place that suitcase," Sheneman told reporters Tuesday.

Authorities also wouldn't say who owns the SUV they were searching. KTVU shot exclusive video of the forensic team and crime scene experts combing through the Kia. A Cadillac in a nearby garage was also being examined, the station said.

Photos of the outgoing girl with dark brown eyes and golden hair were posted all over town, on business fronts, car windows and fire hydrants in the city of about 78,000 people.

Sandra's disappearance sparked a massive search effort around Tracy, about 60 miles east of San Francisco, that included hundreds of volunteers and law enforcement officials, including the FBI, and more than 1,000 tips.

Click here for more on this story from KTVU.com.