In July, Erin Patterson’s ex-in-laws Don and Gail Patterson, and Gail’s sister Heather Wilkinson, died after symptoms consistent with death cap mushroom poisoning.
Heather’s husband, Ian, was released from hospital in September.
The Age reports Patterson has been arrested, and charges have not yet been laid.
Police are understood to be searching her home following the 48-year-old’s arrest.
“Homicide Squad detectives have arrested a woman this morning as part of their investigation into the deaths of three people following an incident in Leongatha earlier this year,” a statement said.
“Four people were taken to hospital on July 30 after they became ill following a meal at a private residence in Leongatha the previous day.
“Two Korumburra women, aged 66 and 70, passed away in hospital on August 4. A third person, a 70-year-old Korumburra man, passed away in hospital on August 5.
“A 69-year-old Korumburra man was released from hospital on 23 September. A 49-year-old Leongatha woman was arrested at her home address shortly after 8am on November 2.
“A search warrant has been executed at the Gibson Street address, with assistance from the AFP’s technology detector dogs.
“The woman will now be interviewed by police and the investigation remains ongoing.”
On July 29, Patterson is alleged to have cooked a beef wellington dish that contained deadly death cap mushrooms before serving it to four people for lunch at her home.
There has been intense media focus on Patterson since news broke of the poisoning. She has denied deliberately feeding the toxic fungi to her guests, claiming she bought them from an Asian grocery store.
“I’m devastated, I loved them,” Patterson said in a video interview in the days after the story broke.
“I can’t believe this has happened and I’m so sorry that they have lost their lives.
Patterson continued to deny any wrongdoing in the police statement and still has no idea how the deadly beef wellington killed her guests.
According to Patterson, the media’s coverage of the incident was wrong and biased, and as a result, she was inadvertently but purposely painted as the perpetrator rather than the innocent party.
How she procured the allegedly toxic mushrooms, how the beef wellington dish was prepared, and what happened to the leftovers are all explained in detail in Patterson’s police statement.
At least three months prior to the lunch, according to the statement, she bought a bag of mushrooms from an Asian grocery store in Mount Waverley. She reported the label on the package of mushrooms she purchased was handwritten.
The meal’s dehydrated mushrooms were combined with additional mushrooms that were bought from a store and cooked into the beef wellington dish, The Age reported.
Police found the dehydrator at the local rubish tip, raising alarms.
Patterson acknowledged in the police statement that the food dehydrator they discovered in a waste bin at the Koonwarra Transfer Station was purposely thrown away. She said in the statement that she had panicked and thrown away the device after she claims that she had been falsely accused of poisoning the food.
In the statement, Patterson claims she too fell ill after consuming the meal on July 31, two days after the dinner party. The Age reported she was admitted to the hospital in Leongatha before an ambulance transferred her to a hospital in Melbourne.
The death cap mushroom is responsible for 90 per cent of all deaths related to mushroom consumption.
All parts of the fungus are poisonous and even eating a small amount can be fatal.
Victim’s ‘miraculous recovery’: Criminologist reveals key to solving case
In September, a criminologist said the investigation into the fatal poisoning could take a major turn as survivor Ian Wilkinson was discharged from hospital after a remarkable recovery.
Forensic criminologist Dr Xanthe Mallet explained that Wilkinson could hold the key to solving the case.
“He’s the only one who attended that lunch to survive besides Erin, and he is going to be giving a full account to police as to what happened at that lunch,” she told Sunrise at the time.
“Who ate what, the demeanours and conversations.”
She said police will also be keen to look into the food dehydrator that Patterson used to preserve the mushrooms before throwing it away at the local dump.
“It’s that dehydrator that potentially cooked the death cap mushrooms that they need to get tested,” she said.