SafeWork SA today announced it had dropped its prosecution of inspection company Safe Is Safe in connection with the death of eight-year-old Adelene Leong, who was killed when she was flung off the Airmaxx 360 ride at the 2014 Royal Adelaide Show.

“Today, SafeWork SA withdrew charges against inspection company Safe Is Safe in connection to the fatal accident at the 2014 Royal Adelaide Show involving the Airmaxx 360 ride,” the work safety watchdog said in a statement released just after midday.

“This decision was made after new information came to light, which meant there was no longer a reasonable prospect of conviction.

“SafeWork SA has also referred this new information to the Office for Public Integrity. No further comment or information can be provided at this stage.”

Minutes later, Independent Commissioner Against Corruption Bruce Lander took the unusual step of revealing an investigation was underway into SafeWork’s handling of the case.

“Ordinarily I would not confirm or deny a complaint or a report had been made to the Office of Public Integrity or whether a particular investigation was underway,” Lander said in a statement.

“However, having regard to the public interest in the prosecution arising out of the SafeWork investigation, and the fact that the prosecution was withdrawn this morning, I felt that it was in the public interest to confirm that an investigation into the matter is underway.”

The statement says SafeWork made a report about the matter to the Office for Public Integrity on Monday.

“The report was assessed by the Office for Public Integrity and referred to me for consideration,” Lander said.

“I have since commenced an investigation into the SafeWork investigation and the evidence that was obtained.”

Both SafeWork and Lander said they would not offer further comment.