SYDNEY (AP) — Australian police on Wednesday were trying to figure out how three people died and a fourth became critically ill after apparently eating wild mushrooms at a family lunch.

Homicide detectives have been investigating the case. Police have interviewed the woman who they say cooked the meal at her home on July 29 but didn’t become ill herself. Police released her without filing any charges but say she remains a suspect.

The woman told media outside her home in the town of Leongatha, in Victoria state, that she didn’t know what had happened.

“I didn’t do anything,” she told Network Nine on Monday. “I loved them, and I’m devastated they’re gone.”

The woman declined to answer questions about what meals were served to which guests or the origin of the mushrooms.

Victoria Police Detective Inspector Dean Thomas said it wasn’t clear what type of mushrooms the guests had eaten, but their symptoms were consistent with those from a death cap, a particularly deadly variety.

Tom May, a principal research scientist of mycology at the Royal Botanic Gardens in Melbourne inspects a Death Cap mushroom as the Victorian Government issues a health alert on March 31, 2021, for poisonous mushrooms after favorable weather conditions have seen an outbreak of the mushroom which is extremely toxic and responsible for 90 percent of all mushroom poisoning deaths. (Photo by WILLIAM WEST/AFP via Getty Images)

He said it would take some time to determine what happened and police were keeping an open mind.

“It could be very innocent but, again, we just don’t know,” Thomas said.

The woman had been hosting her in-laws, Gail and Don Patterson, both aged 70. Both died at area hospitals. Also at the lunch were Gail Patterson’s sister Heather Wilkinson, 66, who died, and husband Ian Wilkinson, 68, a Baptist pastor who remained hospitalized this week in critical condition.

Thomas said the woman who cooked the meal was separated from her husband but police had been told their relationship was amicable. Her children were also at home during the lunch but did not eat the same meal, police said.

Detectives searched the woman’s home on Saturday and took several items. The Sydney Morning Herald newspaper reported that police were also conducting forensic tests on a food dehydrator they had found at a nearby landfill to see if it was linked to the case.