A stack of medical records being shipped from Mexico could tell doctors and detectives whose bones were stashed beneath a Johnston County farmhouse for eight years.

In cases like this, figuring out who is dead and what killed them can be harder than pinning down who did it.

It is a long, tedious process, but in the end, pathologists are certain they will figure out the identity of the bones and unrecognizable body fragments buried on Bobby and Louise Pollard's property. Detectives suspect at least part of the human remains belong to Ceasar Ruvalcava Ortiz. His family in Mexico mailed Ruvalcava's childhood medical charts to help solve the mystery this week.

Pathologists will compare any X-rays and dental records in his chart to the recently excavated remains. Medical examiners hope for an oddity, a bone fracture or deformity, to help them make a certain match. If that fails -- or if detectives want a back-up opinion -- they will send pieces of the remains to another lab for DNA testing against a family member's blood or saliva.

"It's like putting a puzzle together," said John Butts, chief medical examiner for the state, explaining how pathologists generally try to find the owner of decomposed human remains.

"Sometimes our puzzle comes to us intact, and we take it apart," Butts said, not referring specifically to the Pollard case. "Other times, it comes to us in parts, and we reassemble."

Johnston County sheriff's deputies shipped two batches of dismembered body parts, along with two electric saws, to the medical examiner's office in Chapel Hill over the weekend.

The Johnston County Sheriff's Department stormed the Pollards' farm Saturday, less than a day after a tipster -- Sheriff Steve Bizzell won't say who -- told them that a murder took place there in 1997 and a skeleton was hidden there.

A few days before the search, Bobby and Louise Pollard, married for more than 12 years, split ways after a fight, Bizzell said. Louise's mom fetched her, and Bobby went to stay with his mom for a few days.

Detectives struck their first stash Saturday, buried in plastic bags 3 feet under hardwood floors in a hallway off the Pollards' kitchen, Bizzell said. Late Sunday, detectives dug out a chest freezer filled with human remains from under a shed behind the house. A chain saw and reciprocating saw, a power tool that mimics the action of a handsaw, that may have been used to cut up the body were also shut up in the freezer, Bizzell said.

When Bobby Pollard returned home Saturday, deputies stopped him as he drove up the muddy drive to the farm house.

Pollard, a 34-year-old construction worker, is charged with first-degree murder. Louise Pollard, 34 and a homemaker, was arrested later that afternoon and charged with being an accessory for keeping quiet about the bodies for more than eight years.

Detectives also suspect that part of the human remains belong to Ruvalcava's girlfriend, Robin Clark of Wake County, who was 17 when she vanished in August 1997. Medical examiners haven't yet determined whether they have found the remains of two people.

"Literally, when you have fragmentary remains, you lay them out and reassemble," Butts said.

Next, medical examiners try to pin down the person's age, gender and race by studying the bones. If police hand them a name of a possible victim, pathologists try to retrieve X-rays and dental records. The law allows the state medical examiner's office to collect medical records for death investigations, Butts said.

The best way to confirm identity is DNA testing using a family member's blood or saliva. Neither the state medical examiner's office nor the State Bureau of Investigations crime lab can handle these tests, so DNA testing is farmed out to private labs. Those tests cost several thousand dollars each, and local law enforcement agencies must foot the bill, Butts said.

Bizzell said he will insist on DNA testing for the body parts on the Pollards' land. Detectives have lined up a private lab in the Triangle.

It could be weeks before anyone knows for certain who was hidden in the earth between a wilted soybean crop and a thicket of oak trees.