SYDNEY, Sept. 8 (Xinhua) -- An Australian woman who fatally poisoned three members of her family with mushrooms will spend at least 33 years in prison after being handed a life sentence on Monday.

Justice Christopher Beale in the Supreme Court of the state of Victoria on Monday sentenced 50-year-old Erin Patterson to life imprisonment with a non-parole period of 33 years for the 2023 murders of three people, and attempted murder of a fourth.

A jury in July found that Patterson had deliberately served a lunch containing toxic death cap mushrooms to the four guests at her home in the town of Leongatha, 115 km southeast of Melbourne, on July 29, 2023.

The 70-year-old parents of her estranged husband, Don and Gail Patterson, and his aunt, 66-year-old Heather Wilkinson, died from amanita mushroom poisoning in hospital in early August 2023.

Heather Wilkinson's husband, Ian, recovered and was discharged from hospital. Erin's husband, Simon Patterson, was also invited to the lunch but did not attend.

Under the law, Patterson faced a maximum penalty of life imprisonment without the possibility of parole.

The sentence means she will be eligible to be released from prison in the year 2056.

Handing down his decision, Beale called the crime an "enormous betrayal" and said it involved substantial premeditation.

He said that Patterson had invited Simon, his parents and his aunt and uncle to lunch with the intention of killing them all.

"Not only did you cut short three lives and cause lasting damage to Ian Wilkinson's health, thereby devastating extended Patterson and Wilkinson families, you inflicted untold suffering on your own children, whom you robbed of their beloved grandparents."

Prosecutors had called on Beale to sentence Patterson to life in prison without parole, describing the crimes as the worst category of offending. ■