An Australian woman has been apprehended in connection with the suspected poisoning deaths of three individuals caused by mushrooms.

These three individuals fell seriously ill following their participation in a family gathering in Leongatha, a town in Victoria, in July. Another person was hospitalized in critical condition.

Erin Patterson, the person who hosted the gathering, was taken into custody on Thursday, although no charges have been filed against her.

Ms. Patterson, aged 49, has consistently maintained her innocence.

The Victoria Police department has disclosed that Ms. Patterson will be subject to questioning by detectives, and a search warrant has been executed at her residence.

The luncheon guests included Gail and Don Patterson, who are the parents of Ms. Patterson's former spouse, and Heather Wilkinson, Gail Patterson's sister, along with her brother-in-law Ian Wilkinson.

The four were taken to hospital on 30 July reporting violent illness, police say.

Within days the Patterson couple, both 70, and Ms Wilkinson, 66, had died. Mr Wilkinson, 68, later recovered.

Erin Patterson has continued to reiterate her innocence, saying she was taken to hospital after the meal due to stomach pains.

She has said she served a beef Wellington pie using a mixture of button mushrooms bought from a supermarket, and dried mushrooms purchased at an Asian grocery months earlier.

Too sad