(AP) — A 4-year-old boy has died after he fell off a four-wheeler and was run over by the trailer in south-central Wisconsin.

The Columbia County Sheriff's Office says the accident happened Monday night near Portage. Authorities say the boy's father was trying to revive the boy when emergency personnel arrived. The boy was flown to a Portage hospital, where he was pronounced dead.

A preliminary investigation shows the father was using the four-wheeler to pull an empty sprayer tank on a trailer in the yard. Two small children were on the all-terrain vehicle when one fell off and was run over by the trailer.

The name of the boy who died is being withheld until relatives are notified. The Wisconsin Department of Natural Resources responded to investigate the ATV accident.