Erin Patterson invited her former in-laws, Gail and Don Patterson, and Gail’s sister and brother-in-law, Heather and Ian Wilkinson, for a family lunch at her home on July 29 (Picture: Channel Nine)

Erin Patterson – the woman at the centre of an alleged poison mushroom plot which left three people dead – has been arrested.

The mum-of-two, 49, was taken into custody on Thursday morning and questioned at Wonthaggi police station in Victoria, Australia, The Age reports.

No charges are thought to have been laid at this stage. Investigators are believed to be searching her home in Leongatha where the fatal family lunch was held on July 29.

Ms Patterson made beef wellington for her estranged husband Simon’s parents Gail and Don, both 70, as well as Gail’s sister Heather Wilkinson, 66, and brother-in-law Ian Wilkinson, 68.

Ms Wilkinson along with Mr and Mrs Patterson all died days later having fallen seriously unwell, while Mr Wilkinson spent nearly two months in hospital before eventually recovering.

Investigators reportedly believe the group ate death cap mushrooms.

Ms Patterson has always insisted she did not intentionally poison her in-laws and says she was also ill after the meal.

Victoria Police confirmed on Thursday they had made an arrest in the case.

‘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 40 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.’

The death cap is responsible for 90 per cent of mushroom poisoning deaths, The Age reports.

One bite is enough to kill someone, causing severe gastroenteritis and eventually organ failure.

Anyone who becomes unwell after eating a wild mushroom is urged to seek urgent medical care and, if possible, take samples for identification.

Get in touch with our news team by emailing us at [email protected].

For more stories like this, check our news page.

The mum-of-two, 49, was taken into custody on Thursday morning and questioned at Wonthaggi police station in Victoria, Australia.