Three young girls injured after 12 metre fall from Ferris wheel

Law enforcement cordon off the area surrounding the Ferris wheel after three people fell from the ride during a county fair in Tennessee. Photo / AP

Three young girls have plummeted about 12 metres from a Ferris wheel after their basket flipped upside down, leaving one in a critical condition.

The girls, aged six, 10 and 16, tumbled from the ride at the Greene County Fair in the US state of Tennessee about 6.15pm Monday (9.15am Tuesday AEST).

The girls were rushed to Johnson City Medical Centre, where the six-year-old remains in a critical condition with a traumatic brain injury.

Dr Bracken Burns, director of trauma services, said the six-year-old was in the seat with her sister, 10, and the other girl.

Those girls are in stable condition, although the 10-year-old suffered injuries to her forearms. Their names have not been released.

Members of the Greeneville Fire Department help people off the Ferris wheel, which was stopped after three girls fell off it. Photo / AP

A witness told ABC News she screamed at the operator to shut down the ride.

"I was hollering, 'Please stop! Stop! Stop the machine!' It seemed like it was a millennium before it stopped," the witness said.

"I didn't see movement. I'd seen blood coming from their mouth. I actually thought they were dead. It was so horrific."

Witness Gregory Lynthacum said the girls, from two families, fell when their basket appeared to get caught on another basket.

"It was like watching water pouring from a glass," he told WATE.com. "They bounced off the metal bridging of the ride and eventually hit the ground."

A witness said she saw blood coming from the girls' mouths and thought they were dead. Photo / AP

Mr Lynthacum said the ride only stopped after people screamed at the ride operators.

The Tennessee Bureau of Investigation will not assist police with the investigation.

Captain Tim Davis said a third-party inspector will determine "whether there was a mechanical issue" with the ride.

The Green County Fair announced on their Facebook page that all rides will be shut down "until further notice."

Tennessee Department of Labor and Workforce Development said last week there had been four amusement device accidents in the state since July 1, WATE.com reported.

We would like to extend our thoughts and prayers for those injured tonight at the fair. We are deeply shocked and...

Posted by Greene County Fair on Monday, 8 August 2016

The news comes after 10-year-old Caleb Thomas Schwab died after riding the world's tallest water slide, the 17-storey Verruckt, in Kansas over the weekend.

Witnesses said Caleb was "decapitated" after being flung from the ride.