An autopsy on the body of a 19-month-old left in a school van in Rolling Fork Monday affirmed that the child died of heat exhaustion.

The death will also be classified as a homicide, said Sharkey County Coroner Ola Mae Holmes, though whether anyone will face a criminal charge is yet to be determined.

&#8220This is a serious thing,” Holmes said this morning. The autopsy was performed Tuesday night.

Investigators with the Mississippi Bureau of Investigations and Rolling Fork police said they were still looking into the case.

Kaleb Johnson, son of Kenya Johnson and Robert Brady, was picked up from his home in Glen Allan early Monday morning by an employee of Mississippi Christian Family Services, which has an early intervention day-long program for children who have a developmental delay or the potential for such a delay.

The van arrived at the center around 9 a.m. and the nine other children aboard were unstrapped from car seats and taken inside, family and friends said Monday. Kaleb was left on the van as outdoor temperatures rose to 91 degrees. A meteorology expert said the temperature inside the van would have risen to at least 135 degrees. Kaleb’s lifeless body was discovered at about 3. He was taken to Sharkey-Issaquena Hospital in Rolling Fork, where family and friends gathered to seek answers and to mourn.

Warren County District Attorney Gil Martin said investigators continue to search for a lead suspect because, apparently, &#8220several adults were on the bus” that morning before the death occurred.

Information on why Kaleb would have been left on the van and who was responsible has not been made available.

&#8220At this point, we have an ongoing investigation – the details of which are confidential,” said Delores Lewis, media contact for the Mississippi Department of Public Safety. &#8220If we charge someone, we will make a statement.”

If an arrest is made, Martin said, the person or people responsible would be charged with manslaughter, a charge that carries a 20-year sentence.

Coroners rule on the cause and manner of death. In this case, the manner of the child’s death is legally classified as homicide because the actions of others – accidental, negligent or intentional – caused it.