HARRIS COUNTY, Texas (ValleyCentral) — A 5-year-old child died after being left in a hot vehicle on Monday.

Deputies were dispatched to the 13700 block of Blair Hill Lane in Houston, according to a post by Harris County Sheriff Ed Gonzalez.

Upon arrival, it was determined that a child was left inside a vehicle for several hours, and was pronounced dead at the scene.

According to the post, a mother, an 8-year-old child and 5-year-old child were in the vehicle, with the 5-year-old being strapped in a child safety seat.

The mother and 8-year-old exited the vehicle, and assumed the other child got out as well. The post stated that the 5-year-old child typically knew how to unbuckle himself and exit the vehicle, but the car was said to be a “loaner.”

The family was preparing a birthday party for the 8-year-old child at their house that day.

Between two and three hours later, the mother realized the 5-year-old child was “nowhere to be found.” She then ran outside where she found her son in the safety seat.

EMS was called to the scene, and the child was pronounced dead. The case remains under investigation.