A five-year-old boy was found dead inside a van that should have transported him safely to his daycare center in West Memphis, Arkansas Monday. Christopher Gardner Jr. was signed onto the van by his mother at 6:30 a.m. CDT and signed into Ascent Children’s Health Services by employees at 7:15 a.m. CDT – but was never taken out of the vehicle.

Christopher was found dead in his booster seat at 3:30 p.m. ECT, according to the West Memphis Police Department: more than eight hours after he was picked up from his home. With temperatures in the 80s that day, investigators said the inside of the van would have quickly reached 141 degrees Fahrenheit.

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“They didn’t get off their, excuse my language, off their a-- and look,” Christopher’s great grandmother, Carrie Smith, told WMC-TV. “I’m very upset about it. They didn’t look and they can’t tell me they looked. They didn’t.”

Christopher had been attending the facility for developmental issues, as the child previously underwent two heart surgeries. The boy had been regularly going to Ascent since he was just a year old.

“You can see that my great grandbaby suffered in that van,” Smith said. “That wasn’t right.”

Ascent's website described the center as a treatment clinic that provides “quality outpatient and day treatment services to children and their families that are in need of mental health or developmental care.” The website touted specialized treatment programs including physical and speech therapy as well as a “multidisciplinary team of doctors, nurses, psychiatrists, therapists and care staff” with the “training and experience needed to provide comprehensive care for all children and their families who are in need.”

An unidentified former employee told WMC-TV that the facility typically checked the vans three times to prevent just this type of situation from occurring. The employee also noted that there was protocol involving paperwork when checking a child into the facility and that it was mandatory to have at least two adults on the van at all times.

“When we pull up in the front, we blow the horn, they come out and check and then once we go to the back, we get out and check,” the employee, who worked there six months ago, told reporters. “Something was distracting them to not see him on that van all day.”

It remained unclear whether any of the employees at Ascent checked the vehicle after it arrived, or why Christopher was signed into the building when he remained on the bus. The Arkansas Department of Human Services had previously cited Ascent three times for minor issues, though none were related to transportation, according to KTRK-TV.

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The West Memphis Police Department opened an investigation into Christopher’s death, as did the Arkansas Department of Human Services. The case was subsequently forwarded to prosecutors but so far, no arrests had been made.