Denver (AP) The Colorado State Patrol says charges are pending after a 6-year-old boy fell off of a trailer at his family's Livermore farm and hit the ground.

Trooper Gilbert Mares says the boy's father, 33-year-old William Greenwood, was driving a pickup and pulling a homemade trailer behind it Sunday evening. Authorities say the boy was riding on the trailer, but fell off.

The trailer then struck the boy, causing serious injuries.

Nicholas Boaz was taken to the Medical Center of the Rockies in Loveland, and later airlifted to the Children’s Hospital in Aurora.

His condition is unknown.