An Australian pilot has had his conviction for the murder of an elderly camper overturned on appeal and will face a retrial.

Greg Lynn was sentenced last year to a minimum of 24 years in prison for the 2020 murder of 73-year-old Carol Clay at a campsite in Victoria.

But on Thursday the state’s Court of Appeal ruled there had been “serious irregularities” during the trial and ordered a retrial.

Court of Appeal President Karin Emerton said there was a “substantial” likelihood that a miscarriage of justice had occurred during the original trial.

Lynn, 59, was found guilty of killing Clay during an altercation in Victoria’s Wonnangatta Valley in March 2020 but acquitted over the death of her boyfriend, Russell Hill, 74.

He had pleaded not guilty but admitted to moving the bodies of Ms Clay and Mr Hill before torching their campsite and later burning their remains.

The case, which sparked one of Victoria’s largest missing person operations at the time, gripped Australia.

Lynn was stood down as a pilot by Jetstar – a budget airline owned by Qantas – shortly after his arrest in November 2021.

During his five-week trial last year, Lynn told the jury in Victoria’s Supreme Court that he was involved in an altercation with the couple because he was hunting in the area.

His lawyers said that he had then killed the two during two separate struggles for control of a shotgun and a knife – but that it was not murder because the deaths were accidental.

Prosecutors argued he had likely shot Ms Clay after killing Mr Hill.

His lawyers later appealed his sentence and conviction on four key grounds. They alleged prosecutors at his trial had breached “the rules that govern the fair conduct of criminal trials” on multiple occasions.

Lynn was remanded in custody and will appear in court again on 28 January.