Relative of Australia killer Ivan Milat admits murder

Ivan Milat was convicted of seven killings in 1996

The teenage relative of notorious Australian serial killer Ivan Milat has pleaded guilty to the brutal axe murder of another teenager.

The boy, who cannot be named for legal reasons, admitted killing 17-year-old David Auchterlonie.

Mr Auchterlonie's body was found in Belanglo State Forest, south-west of Sydney, last November.

It is the same forest that Ivan Milat dumped the bodies of seven backpackers he killed between 1989 and 1992.

According to papers filed with Sydney's Campbelltown Children's Court, the teenager bragged to a friend the day after the killing: ''You know me, you know my family... I did what they do."

He is said to have gone with Mr Auchterlonie and two other friends to Belanglo forest on the night of 20 November 2010.

The murder and the conversation leading up to it were captured in a video recording on one of the friends' mobile phone.

The teenager accuses Mr Auchterlonie of telling people about money he had stolen - an accusation the victim is heard denying.

According to court papers, the accused coaxes Mr Auchterlonie out of the car and swings an axe into his torso.

"Over the next 10 minutes (the boy) stood over and threatened the deceased with the axe," according to court documents.

Mr Auchterlonie pleaded for his life, but sounds of the axe hitting him can be heard on the recording.

The accused and another boy covered the victim's body with branches before all three left the forest.

The teenager - who reportedly showed no emotion when his lawyer entered his guilty plea - is due to be sentenced on 2 December and could face life in prison.