A young man accused of killing his ex-girlfriend whose body was found inside a burnt-out car has pleaded guilty to her murder.

Lachlan Young, 21, has been on trial for the murder of his former partner Hannah McGuire in April 2024.

WATCH THE VIDEO ABOVE: Hannah McGuire’s killer pleads guilty

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Young had admitted he killed McGuire but denied he murdered her, instead offering to plead guilty to manslaughter.

That offer was rejected by prosecutors at the start of his murder trial.

However, on Friday Young changed his plea to guilty.

McGuire’s family was in court and clapped when the plea was made.

The 23-year-old’s body was found in a burnt-out car in a state forest in Scarsdale, southwest of Ballarat in Victoria.

Young admitted he burnt her body in her own car on April 5, 2024.

However, the matter went to trial as he pleaded not guilty to murder and claimed McGuire’s death was an “unplanned and spontaneous event”.

The Supreme Court jury trial began on July 9 in Ballarat, regional Victoria, where the murder occurred.

Jurors did not sit on Thursday, but returned 10.30am on Friday when Young pleaded guilty to murder.

He will face a pre-sentence hearing at a later date.