POLICE have broken their silence after a woman fell from a ride at the Cairns Showfest while hundreds of people looked on in horror.

The Hangover, an inverted pendulum ride, has been taped off by police and will remain in place while Workplace Health and Safety conduct an investigation into a horror fall on Saturday night.

The WHS investigators attended the scene on the night of the fall.

"We are still holding that scene until investigations have been finalised," Acting Inspector Brett Jenkins said.

"The ride will remain in situ until all investigations are complete.

"It will to go on for as long as it takes."

He would not comment about the co-operation of show organisers with police following the accident.

He said the 25-year-old woman was in a stable condition and "closely monitored" at Cairns Hospital's intensive care unit.

A Queensland Ambulance spokeswoman said the woman fell 30m from the pendulum and suffered serious and traumatic injuries.

A/Insp Jenkins said the woman's family were grateful for the support of emergency services following the accident and "most respectfully have asked that people not make any speculation about the incident on social media".

"Investigators have requested that anyone with any knowledge about the incident, particularly any footage, to make themselves known to police," A/Insp Jenkins said.

"Any information is crucial to the investigation."

Originally published as Police break silence over horror Cairns Showfest fall