What we know about the couple killed at a nudist ranch in California

A husband and wife who settled at a nudist ranch nestled in a remote California canyon had been missing for days when a 911 call steered police to the house next door.

Their neighbor, Michael Royce Sparks, 62, has been charged with two counts of murder after police said he admitted to killing two people and human remains were found at his home. Authorities have confirmed the victims were the missing couple – Daniel Menard, 79, and his wife, Stephanie Menard, 73.

Since his arrest, Sparks has remained in custody and is expected to appear in court later this week. CNN has been unable to identify an attorney for Sparks or locate family members.

Redlands Police Chief Rachel Tolber said Tuesday she had never seen “this type of case” and it was “certainly concerning.”

As authorities search for a motive, here’s what we know about their deaths and the investigation so far:

The couple

The Menards lived in the Olive Dell Ranch resort in Southern California’s San Bernardino County, about 65 miles east of Los Angeles near the cities of Redlands and Colton. The 100-acre property has RVs and mobile homes where residents have lived for years. Others have visited for short-term stays, including during the resort’s annual 5k run.

Irene Engkraf, a neighbor of the Menards, told reporters the couple enjoyed playing poker, gathering with friends for karaoke and attending Bible study and church service on weekends.

“It felt so odd not having Stephanie sitting right next to me (at church) but I know God is with them, he’s with them wherever they are, and I can see them holding each other’s hands,” Engkraf said.

The couple was last seen at the home on August 24. The next day, Engkraf said she became worried when the Menards didn’t attend Sunday church service as usual. Their dog, a white Shih Tzu named Cuddles, was also missing.

She first saw the Menards’ car sitting “abandoned” down the road from their home, and later entered the couple’s home using a spare key but found no signs of them. Stephanie’s purse and both of the Menards’ phones were there and their bed was empty, Engkraf said.

Neighbor Tammie Wilkerson told CNN affiliate KCAL the Menards were a loving couple who took care of each other.

“Stephanie was a bit of a spit fire. She told you what she thought. She didn’t have any problem doing that and she took care of Dan so well,” Wilkerson said.

The suspect

It wasn’t until several days had passed following the Menards’ disappearance that police received a tip from Sparks’ family, which prompted his arrest and a days-long search for evidence at his home.

A family member called 911 saying Sparks was involved in the Menards’ disappearance, adding he “had admitted to killing two people and was threatening suicide,” Tolber, the police chief, said Tuesday.

“I believe that there may have been other people that were texted, but the initial call that started our focus on him was from the family,” Tolber said.

Officers arrived at Sparks’ mobile home and found him hiding inside a 5-foot-deep concrete space under the home. San Bernardino County District Attorney Jason Anderson described the space as similar to a “homemade basement” underneath the home.

Before police could arrest Spar ks, they had “lengthy negotiations” with him because he was armed and barricaded, Redlands Police Department spokesperson Carl Baker said Friday. Sparks attempted to shoot himself but his weapon misfired, police said.

Engkraf, the neighbor who reported the Menards as missing, described Sparks as a “loner” who “didn’t socialize so much.”

The discovery

After Sparks’ arrest last week, authorities searched his home and found human remains, police said. The San Bernardino County Sheriff-Coroner Department confirmed Thursday the remains were those of the Menards.

Their cause and manner of death has not been determined, a spokesperson for the coroner’s office told CNN.

Police do not have a reason to believe there are other victims, Tolber said on Tuesday.

The search took days because of the state of the property, its potential collapse and the need to remove debris with heavy equipment, police said.

The Menards’ dog was not found during the search, police said.

The unclear motive

Wilkerson, their neighbor, called the Menards “very sweet people” and said “there’s no way” they could have walked away from their car.

“There’s not a mean bone in their body at all, which makes this very confusing,” Wilkerson said.

While authorities have not shared details about a potential motive – other than that it did not appear to be planned – neighbors discussed with reporters an ongoing feud between Sparks and the Menards.

Wilkerson told CNN affiliate KABC she was aware there was tension.

“When I first moved here, he told me how much he hated them, and he hated Dan specifically because Dan would cut the tree … trim the tree down,” she said.

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