OMAHA, Neb. (AP) — A 1-year-old girl died after being left inside a day care center’s van on one of the hottest days of the year, and the driver of the van was arrested, police in Nebraska said Tuesday.

Officers and medics were called Monday afternoon to Kidz of the Future Childcare in Omaha for an unresponsive baby inside the van, police said. The call came as temperatures reached into the upper 90s (mid-30s Celsius) and the heat index soared to around 110 degrees (43 Celsius), part of a heat wave plaguing the Central U.S.

The child was rushed to a hospital but pronounced dead, police said.

Police issued a statement Tuesday saying a 62-year-old man who was driving the van was arrested on suspicion of child negligence resulting in death.