Greeneville police Capt. Tim Davis said a basket reportedly overturned on a Greene County Fair ride and dumped the occupants out.
They fell 35 to 45 feet and were taken to the Johnson City Medical Center -- two by helicopter and one by ambulance, he said. All are alert and talking to hospital staff, Davis said.
Eyewitness Gregory Lynthacum said the car the girls were riding in appeared to "get caught" as the wheel lifted upward, CNN affiliate WJHL-TV reported
"It was like watching water pouring from a glass," Lynthacum told the station. "They bounced off the metal bridging of the ride and eventually hit the ground." Operators finally stopped the ride after people on the ground screamed at them, Lynthacum said.
No other details regarding the incident or the injuries were immediately available. Photos shared to social media show at least one of the ride's baskets nearly upside down.
The Tennessee Bureau of Investigation has been called in, CNN affiliate WATE reported.
The accident follows the death of a 10-year-old boy
on a water slide at Schlitterbahn water park in Kansas City, Kansas. The Sunday incident is being investigated by Kansas state police.
Caleb Thomas Schwab was killed while riding Verrückt, the world's tallest water slide.
Thousands of children are hurt annually on amusement rides, according to a 2013 study by Nationwide Children's Hospital in Columbus, Ohio. The study examined data from the Consumer Product Safety Commission.
Head and neck injuries were the most common at 28%, with 1.5% of the injuries requiring hospitalization, the study said.
Consumer Product Safety Commission statistics for 2015 are not available, but a review of the raw data found 45,000 injuries associated with amusement rides and water slides nationwide. About 30,000 of these cases involved those under age 18.
In 2013 at a Connecticut festival,13 children were injured in a swing ride, some seriously.
The ride "apparently lost power causing the children on the ride to forcefully fall to the ground," Norwalk police said at the time.