A 5-year-old boy died Monday after workers at an Arkansas childrens health clinic allegedly left him in a hot van, police said.

Authorities were called to Ascent Childrens Health Services in West Memphis around 3:30 p.m. Monday, after Christopher Gardner, Jr. was found in one of the vans booster seats. Paramedics were unable to resuscitate the child, police said.

Christophers mother told Memphis WMC Action News the van picked her son up around 6:30 a.m. that day. Authorities said the van arrived at the clinics day care center about 45 minutes later. Records kept by the facility show someone signed the boy in that morning indicating he was present, WREG News reported .

The West Memphis Police Department said they suspect the child was left unattended for at least eight hours, on a day when outside temperatures reached 80 degrees.

In addition to a driver, an adult passenger is reportedly assigned to each van to ensure the safety of the passengers.

They didnt get off their, excuse my language, off their ass and look, Christophers great grandmother, Carrie Smith, told WMC Action News. Im very upset about it. They didnt look, and they cant tell me they looked.