The convicted mass murderer wanted to know details of the weekend killing of 17-year-old David Auchterlonie.

Milat tortured and killed seven young people and dumped their bodies at Belanglo, south NSW, during the mid-1990s.

A source inside the Supermax high-security facility at Goulburn, where Milat is serving seven life sentences, said last night: "He chuckled a bit and asked some questions."

A spokesman for Corrective Services would not comment on Milat's reaction, but confirmed he had access to daily newspapers and would be able to read about the developments in the case.

The sickening reaction to the murder came as a court heard gruesome details of how a teenage male relative of Milat's allegedly lured the victim to the Belanglo forest, chased him around the car with a double-bladed axe, and then fatally struck him on the head.

Police allege Milat's relative had been pressuring a number of friends to accompany him to the notorious forest for up to a week before the killing on Saturday night.

Two other men, Cohen Klein, 18, and another 18-year-old man who cannot be identified, told police they cowered in the car after they allegedly witnessed Milat's relative strike David to the left side of his body, then chase him with the axe along a dirt track into the bush.

While in the bushland, it is alleged Milat's relative took another swing with the axe and fatally struck David in the back of his head.

Police allege the killer then directed Klein and the other man to help him dispose of David's body and to cover it with debris.

Both men have been charged with being accessories after the fact to murder and refused bail.