The family of a woman murdered by a serial killer is pleading for him to remain behind bars.

Reginald Arthurell will be up for parole on Thursday after the murder of three people.

Police are investigating claims the 75-year-old told another inmate of his plans to blow up NSW Police headquarters and kill the family of one of his victims.

Arthurell is believed to have said he will kill the family members of his fiancee Venet Mulhall, who he bashed to death with a piece of wood in her central New South Wales home in 1995.

Ms Mulhall’s brother Paul Quinn, who found his sister’s body, told Ben Fordham he’s feeling very anxious upon Arthurell’s release.

“This is legal insanity. Three killings, three times on parole, that’s just not on.

“The man is a psychopath and he thinks nothing of killing another human being.”

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