An Alabama woman who was missing for 12 days was later found dead in a parked, unoccupied police van in Huntsville, police said.

According to the Huntsville Police Department, an officer discovered 29-year-old Christina Nance's body in the van, which was parked in a police department lot, on Oct. 7.

Nance's family had not seen her since Sept. 25 and reported her missing on Oct. 2. A police officer discovered her body five days later. City cameras captured Nance entering the unoccupied van at about 12:30 p.m. on Sept. 25, Huntsville Police Deputy Chief Dewayne McCarver told reporters at a news conference last week.

Autopsy results from the Madison County, Ala., coroner's office showed no foul play or trauma in Nance's death, according to police.

Her official cause of death will be determined by the Alabama State Medical Examiner once further tests are complete.

Family members, who viewed the parking lot surveillance footage ahead of the news conference, are now calling for an investigation into her death.

"The video was not clear enough to indicate that that was our sister Christina Nance" climbing into the van, her sister Whitney Nance told local news station WAFF.

The surveillance footage released Friday shows Nance walking around a parking lot, lying down in the bushes, and sitting on the hood of a police car.

McCarver said she later walked up to other parked and unoccupied vehicles for about 10 minutes before entering the parked police van. According to the video footage, it appeared there was no one else present when Nance got inside the van.

The officer who found Nance's body says they observed shoes next to the parked van, approached the vehicle and discovered her body inside.

McCarver told reporters that the van was unlocked, which violates "department policy" and "shouldn't have happened."

"All city vehicles should remain locked any time they are not in use or occupied," McCarver said. "Sometimes, you just have to say that was something that shouldn't have happened. It did."

The police van, according to police, was purchased in 1995 and was initially used to transport inmates to jail. However, in the early 2000s, the van was repurposed and used by employees to "transfer evidence" approved for destruction from cleared investigations.

"Because of its original design, it does not have handles inside. It was made for transporting inmates," McCarver said. "You cannot exit once you're inside."

The van was last used in March 2021, police said.

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