Mushroom lunch Erin Patterson arrest: Five key pieces of evidence cops are ... trends now
The investigation into the mushroom poisoning deaths that have haunted Victoria's Gippsland region for months had a major development on Thursday as Erin Patterson was arrested.
Patterson, 48, cooked a beef Wellington pie that is suspected to have been laced with death cap mushrooms for a family lunch at her Leongatha home, in the state's southeast, on July 29. She has not been charged with any offence.
Three of her four guests - her former parents-in-law Gail and Don Patterson, both 70, and Gail's sister Heather Wilkinson, 66 - later died after presenting to hospital with severe symptoms, which were at first mistaken as gastro.
Heather's husband Ian, 68, spent weeks in hospital fighting for life before miraculously pulling through after receiving a liver transplant.
Patterson has previously denied any wrongdoing and said she could not explain why the group fell ill after eating the dish.
But more than two months on, the baffling case took a huge turn on Thursday as detectives took her in for questioning while simultaneously raiding her home.
As her police interview continues, Daily Mail Australia looks at the clues police have been investigating throughout the months-long investigation.
Erin Patterson is pictured speaking to reporters outside her Leongatha home in August
1. The mushrooms
In the days after the four guests fell ill, medical teams at hospitals in Melbourne (where they were later transferred) began to suspect they had ingested death cap mushrooms as their livers rapidly deteriorated.
Forensic tests confirmed in late September the three deaths were indeed the result of death cap mushroom poisoning.
Due to the highly-regulated nature of the mushroom industry, experts say it is extremely unlikely poisonous fungi could make its way onto supermarket shelves.
As such, police early on in the investigation announced they were treating the case as suspicious.
Daily Mail Australia does not suggest Erin was responsible for any of the poisonings or deaths.
Pictured: The local tip where police found and seized a dehydrator
2. The food dehydrator
Death cap mushrooms, which are found under oak trees, grow in the wild around Victoria's Gippsland region during warm, wet, weather.
Autumn presents the ideal blooming conditions for mushroom growth and state health officials usually issue warnings in April for Victorians to be wary of consuming wild mushrooms.
As the deadly lunch was held in winter, death cap mushrooms were no longer in season.
On August 4, the same day Gail and Heather died in hospital, police seized a food dehydrator - which are used to dry out vegetables for cooking at a later time - from the local tip.
The cooking device was sent away for forensic testing early during the investigation to determine if it contained death cap mushroom spores, with police yet to publicly reveal the results.
In a statement later handed over to police, Erin admitted to dumping the food dehydrator at the tip 'in a panic' after her ex-husband Simon Patterson accused her of poisoning his parents.
She added that she had initially lied to police when she told officers she dumped the device a 'long time ago'.
Gail and Don Patterson died after eating the mushrooms
Ian Wilkinson and Heather Wilkinson (both pictured) became severely ill after they ate wild mushrooms. Mrs Wilkinson died in August while her husband was released from hospital in September after spending weeks fighting for life
3. Erin's statement
In the hours after Don died on August 5, detectives searched Erin's home and took her in for questioning.
She provided a 'no comment' interview and was released later that night.
However, nine days later she submitted a detailed statement to investigators about the lunch, saying she regretted previously not speaking to detectives under instruction of her lawyers.
In the statement, Erin claimed she used a combination of mushrooms in the dish - with some bought from a local supermarket while the others came from an Asian grocer in Mount Waverley, in Melbourne.