According to the Riverside County Sheriff's Office, deputies and Cal Fire crews responded to the 20700 block of Cereal Street Sunday around 10 a.m.
When they arrived, they found a group of good Samaritans performing life-saving measures on the girl, identified as Brooke Carlton.
Brooke was at a track designated for off-road vehicles riding an electric motorbike and was struck by another child who was also riding an off-road motorbike, the sheriff's office said.
The other child was treated at the scene for minor injuries, and Brooke was taken to the Inland Valley Medical Center where she later died.
"We are truly sad about the situation," the venue said in an Instagram post Monday morning. "This was such a freak accident as the parent said. This is not a time to bash the track but a time to remember this little girl and support her family. We are a community and we will do our part in supporting the family as well. May you rest in peace Brooke!"
Meanwhile, a GoFundMe page has been set up to help the family.