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Police are investigating whether a West Australian man convicted of hacking to death a woman and her three children with an axe sent a threatening letter to his victims' family.
Barbara Marchant, the mother of the murdered woman, says she received a letter in October from someone who could have been William Patrick Mitchell.
Mitchell was sentenced to life imprisonment for the horrific 1993 killings at a farm house in Greenough, 400km north of Perth, almost 14 years ago to the day since Ms Marchant received the letter.
Ms Marchant said the letter was addressed to "Grandma Marchant" and signed "William".
"Found you bitch," she told ABC Radio the letter says.
"Had someone look for you. Got a photo of your little girl - short hair, white shirt and little skirt, nice. See you when I get out."
Ms Marchant, who lives in Queensland, said the letter fitted the description of her 11-year-old granddaughter.
"It makes it scarier than ever, especially when they have a description of my granddaughter," she said.
Queensland police say they are investigating the matter.
"We have received a complaint regarding that incident and police are making investigations, and are liaising with West Australian police in regards to that," a Queensland police spokeswoman said.
WA's Department of Correctional Services is being sought for comment.
Ms Marchant said she had not heard back from police since her complaint three months ago and still did not know if it really was Mitchell who sent her the letter or whether it was a hoax.
"I want to find out where it came from, and if it did have anything to do with him, I just want him to stay in there, I don't want him to do it to anybody else."
Mitchell used an axe to brutally murder Karen MacKenzie, 31, and her three children Danny, 16, Amara, 7 and Katrina, 5, on February 22, 1993.
He was sentenced to strict life imprisonment with a minimum 20 years but could be eligible for parole in 2013.
- AAP
