The California neighbor charged with killing an elderly couple inside a nudist ranch hated his alleged victims as police found human remains beneath his home, according to a report.

Redlands Police recovered the human remains from a concrete bunker under Michael Royce Sparks’ home just after 2:30 p.m. Friday.

“Members of the Redlands fire department, certified in confine space operations, entered the space beneath the suspect’s home and began to remove bags of evidence,” Redlands Police spokesman Carl Baker said during a press conference.

“At this time I can confirm the presence of human remains under the house,” he added.

The gruesome discovery came less than 24 hours after Sparks was arrested and charged with the murders of Stephanie and Daniel Menard, who have been missing from the Olive Dell Ranch nudist resort since Sunday.

Cadaver dogs alerted police to the underground space where Sparks was pulled from Thursday night.

Police were executing a search warrant on Sparks’ residence on Thursday when the suspect did not cooperate leading to police using an armored police vehicle with a hydraulic battering ram that tore through the home.

Sparks, 62, was discovered underneath his home and “surrendered voluntarily last night after lengthy negotiations,” Baker said Friday.

Investigation operations were suspended until Saturday morning as the underground structure showed signs of potential collapse.

The San Bernardino County Coroner’s Office is examining the remains but has not confirmed if they are the missing couple.

The Menards and their dog, a Shih Tzu named Cuddles, were reported missing by a friend last Sunday after they were last seen leaving their home a day earlier.

Police say the Menards’ unlocked vehicle was located down the road from their home the same day, as Stephanie Menard’s purse was located inside her residence along with her and Daniel’s cell phones.

Tammie Wilkerson, another Olive Dell Ranch nudist resort member, revealed Sparks seemingly had deep hatred for his elderly neighbors.

“He didn’t like them,” Wilkerson told KCAL. “He hated them and he told me that many times.

“It’s such a stupid reason,” she explained. “They had a tree that was on their property line and Dan used to go trim the limbs and (Sparks) hated that. That formed his hatred towards them.”

Wilkerson claims she drove Sparks, who was known by his neighbors as “Sparky” to the store several times so he could buy materials for the underground shelter.

“I couldn’t imagine someone would buy bags and bags of cement, almost every other day,” Wilkerson told KABC. “I asked him one time, I said, ‘Sparky, what are you doing with all the cement?’ and he’s like, ‘I’ve got someone projects I’m doing,’ and I’m like ‘ok.'”

Other neighbors say they were unaware of the tension between Sparks and the Menards.

“Always cordial, always respectful, never aggressive, never mean, just a very sweet person,” Christopher Hernandez told the outlet about Sparks.

Police have not revealed a motive behind the suspected killings.

Sparks is being held without bail at the San Bernardino West Valley Detention Center.

He is scheduled to appear in court on Sept. 3.