On Thursday, homicide squad detectives arrested Patterson, 49, at her home in Leongatha, a bucolic country town about 70 miles southeast of Melbourne, shortly after 8 a.m. local time. They also began to search the property, including using detection dogs.
Patterson has not been charged and denies any wrongdoing. In Australia, suspects can be taken into custody for questioning before charges are filed. “The investigation remains ongoing,” Victoria Police said in a statement Thursday.
The guests at the July lunch — the host’s in-laws, Don and Gail Patterson, both 70; and a local pastor, Ian Wilkinson, 69; and his wife, Heather Wilkinson, 66 — were served beef Wellington, a traditional pastry-based dish that includes mushrooms. That night, they all became seriously ill with what appeared to be food poisoning. Ian Wilkinson spent nearly two months in the hospital. The other three died.
The case garnered international attention and triggered safety warnings about the dangers of foraging for wild mushrooms.
Death caps look similar to other nonpoisonous mushroom species. That makes them easily mistakable to people who forage for them in the wild. Just half a cap can cause liver damage. A possible antidote is available in Europe but is awaiting approval in the United States and elsewhere.
In an account provided to police and the Australian Broadcasting Corp. in August, Patterson said she used two types of mushrooms in the beef Wellington dish: button mushrooms from a supermarket chain and dried ones from an Asian grocery store. She also said her estranged husband — who had been due to join them at the lunch but canceled — had accused her of killing his parents. Patterson wrote that after the meal, she, too, was hospitalized with stomach pains and diarrhea and was put on a saline drip. Her two children also ate the leftovers the next day — minus the mushrooms, which she scraped off because they didn’t like them, she wrote.
Commercial mushroom sales slowed in Australia after the case, although growers said it was impossible for the deadly varieties to make it into stores.
Adam Taylor contributed to this report.