“The matter needs to be dealt with by us,looked at[by] us,and determined by us thoroughly what’s actually occurred,and using the evidence that we have to determine and understand exactly what’s happened and if we can explain what caused the deaths.”

Steendam said she was uncertain if the statement was handed to the media before it was given to police.

Patterson,48,said earlier this week she was voluntarily providing a statement because she now believed it had been a serious mistake to provide a “no comment” interview to investigators,which she said was based on advice provided by a lawyer who no longer represented her.

Steendam would not be drawn on the contents of the statement or whether she believed it was an accurate account of what occurred.

“I don’t think it’s helpful to actually comment further on this investigation,” she said. “It is an active matter and when we have more to say publicly,we’ll do that. But I think to speculate or to talk about the aspects of the investigation in detail is unhelpful.”

She also warned the investigation would be lengthy and said police had been “very clear” to date that the three deaths were unexplained at this stage.

“We’re keeping an open mind about what has actually occurred,” Steendam said.

“I understand the interest and the desire to have more information about this,but given it’s an active investigation … I am limited in what I actually can say about the matter,except to say,it’s not going to be quick.

“This needs to be investigated thoroughly. We’re working with the health department,and we will take as much time as needed to understand what’s occurred and whether or not there are matters that we need to further investigate.”

Speaking toThe Australianearlier this week,Patterson said she felt as though she had been “painted as an evil witch” and had been trapped in her home.

Her comments came as media outlets continued to park outside Patterson’s house. Patterson said she had not been able to have friends over to support her because “nobody wants their face in the media”.

Earlier this week,the Australian Mushroom Growers Association said it was impossible that a grower could produce poisonous fungi.

“This fungus[death caps] only grows in the wild,” the association said in a statement. “Commercial mushrooms are grown indoors in environmentally controlled rooms with strict hygiene protocols and food safety standards.

“The only mushrooms you can be sure are safe are fresh,Australian-grown mushrooms bought from a trusted retailer.”

In Patterson’s legal statement,quoted by the ABC,she confirmed her estranged husband Simon Patterson had accused her of killing his parents.

Patterson said in the statement that she was worried she would lose custody of their children anddumped the dehydrator in the tip after panicking.

“I am now devastated to think that these mushrooms may have contributed to the illness suffered by my loved ones,” she wrote.

Earlier this week,homicide squad detective Dean Thomas said Patterson remained a suspect because she cooked the meals.

But he also said police were still considering an accidental poisoning “not at the hands of somebody else” to be a possibility,alongside potentially “nefarious activity”.

With Chris Vedelago and Marta Pascual Juanola

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