More gruesome details came to light on Tuesday regarding the gruesome murder of 77-year old Johanna Christy, who was found dismembered and buried in her own backyard.

The chilling information was obtained from the arrest affidavit of her grandson, 28-year old David Christy, who has now been officially charged with the murder.

"This is not the kind of crime that happens in Corpus Christi," District Attorney Mark Skurka said. "Clearly a terrible tragedy took place with this lady."

Skurka calls this murder one of the most brutal he's seen in his 25-year career as a prosecutor, and one look at the arrest affidavit, a synopsis of the crime report of David Christy, explains why. It lists what police officers saw from the moment they arrived at the crime scene in the 3800 block of Bentwood Drive.

The first officer at the Christy home writes, "The area in the backyard was soft and recently turned over."

That was just before backup police reported that Johanna Christy's body was found buried in the backyard. The report also states that the body had been cut up with a chainsaw into four parts; that it happened in the garage of the house; that the assailant placed the torso in a black plastic trash bag and then buried the torso and the rest of the body in the backyard.

The details also included excerpts from the Nueces County Medical Examiner, who determined that the elderly woman died from blunt force trauma to the head.

"It's pretty clear, one thing, she was not alive when the dismemberment took place, thank God," Skurka said. "There's just a lot of details about this case that may come out later that are kind of unsettling."

Police were initially called out to the Christy home last Monday evening after a relative contacted the Corpus Christi Police Department about a welfare concern. Christy's son, who lives in San Antonio, told police he hadn't heard from his elderly mother in several days.

David Christy ran from the crime scene and fought with police. He was eventually arrested. He remains in custody at the Nueces County Jail, charged with murder, tampering with evidence and evading arrest. His bonds total $300,000.