Bullhead City police said an 8-year-old girl whose body was found Wednesday in a shallow grave near her home was strangled to death.
The prime suspect in the case, Justin James Rector, was arrested Thursday morning on suspicion of kidnapping and first-degree murder.
Police said the Mohave County Medical Examiner determined Isabella (Bella) Grogan-Cannella died from asphyxiation by strangulation.
Bullhead City Police Chief Brian Williamson said the medical examiner earlier confirmed the body found in a shallow grave near the victim's home is that of Isabella.
Rector, 26, of Bullhead City, was described as a family friend who had stayed at the girl's home for the past few days, police said Thursday afternoon.
Rector was taken into custody Tuesday night on shoplifting charges after he stole clothes from a local Walmart store, Williamson said.
Williamson said a Mohave County search and rescue team came across the body around noon Wednesday. He said shoe prints found at the site matched those of Rector's.
He said his department has not ruled out other arrests in the case.
Isabella's mother reported her missing early Tuesday after she wasn't in her bed around 1:30 a.m.
Police learned that Monday night, the girl's mother, her husband, her mother-in-law, four of her friends, including Rector, and three children, including Isabella, where at the home. The girl's mother left Isabella and her 10-year-old child with her mother-in-law and Rector while she and the others went to Walmart, according to the police report.
After learning Rector left the home the same time Isabella disappeared, police began searching for him and found him on Highway 95 in the area of the Walmart at about 3:30 a.m. Police said he had just stolen a pair of shoes, underwear and a shirt from Walmart and admitted to hiding his old shoes inside the store and hiding his old shirt along the highway.
Police said Rector could not provide his whereabouts in the three hours from when he left Isabella's mother's house to when he arrived at Walmart. He was arrested for shoplifting and remained in custody while police investigated.
In the days following her disappearance, personnel from the Bullhead City Fire Department joined with police and volunteers to canvas the neighborhood and nearby park and river areas. A helicopter had also been searching for the girl.
The Gilbert Fire Department's Child Abduction Response Team (CART) was deployed to help with the search.
Detectives said she was dressed in the same shirt as the night she disappeared but was found with no shorts. The FBI found shoe prints matching Rector's old shoes in the wash area of the desert where Isabella was found, according to the police report.
Rector was interviewed and did not deny the murder, but stated that he could not talk about it and requested an attorney, the police report states.
The FBI and National Center for Missing and Exploited Children also assisted in the investigation.
Rector's preliminary hearing is scheduled for 9 a.m. on Sept. 12.
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