He Was Buried in 'Makeshift Tomb' Under Stairs for Nearly 8 Years. Prosecutors Think They Know Who Put Him There

Eric Israel “Neno” Mercado left his California home on October 11, 2014. No one saw him return.

His family created missing persons posters which they circulated on a Facebook page dedicated to his disappearance.

In September 2019 — about five years after Mercado was last seen — the San Bernardino Police Department issued a formal missing persons poster.

Now, his ex-girlfriend, Trista Ann Spicer, will face trial on a murder charge.

Spicer's most recent ex turned her in, The San Bernardino Sun reported from the courtroom last week.

Spicer — who is charged with felony murder and of use of a deadly weapon — has previously pleaded not guilty in the case, according to her online court record. (Her lawyer, Gary W. Smith, did not respond to PEOPLE in time for publication.)

At the preliminary hearing Friday, June 21, the ex-boyfriend, Waylan Gentry recalled a conversation the couple had in 2022 ahead of her planned move to Illinois, per the newspaper.

“She said she needed to take care of something first. She needed my help,” Gentry testified, alleging that she eventually told him she needed his help to “get rid of” her ex. 

“I didn’t know what she meant,” Gentry told the court. “She said he was buried under the stairs. I did not believe her.”

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Gentry alleged that Spicer proceeded to detail a night in 2014 in which she had approached her boyfriend sleeping, who was on their loveseat, before hitting him over the head with a frying pan, cutting his throat with a box cutter and stuffing his body in her backyard storage area.

On August 23, 2022 — about eight years after Mercado’s disappearance — San Bernardino Police Homicide detectives searched Spicer’s home “for possible human remains,” according to a press release from the time. There, they allegedly found “a makeshift tomb on the property,” and, entering the tomb “located human remains inside.”

The San Bernardino Sun reported that investigators allegedly found Mercado’s body wrapped in a sliced-open air mattress. 

Detective Tiffany Montez testified, per the newspaper, that Mercado’s nose and eye socket were “obliterated” and that the medical examiner told her that the force of the frying pan against Mercado’s head would have killed him “within seconds.”

Gentry testified that Spicer claimed Mercado often beat her. In a 2022 interview in The San Bernardino Sun, his family said they believed the couple to get along.

During the preliminary hearing, the judge allowed Spicer — whose hands and feet were shackled — to have her handcuffs removed so she could take notes, the newspaper reported.

During proceedings, prosecutors presented photographs of two couches inside the home, the back of the couch and an outdoor staircase, per the court’s portal minute order obtained by PEOPLE.

Spicer is set to return to court on July 12 at 8:30 for an arraignment on the criminal information.