A dozen members of a religious group have been arrested over the death of an eight-year-old girl in southern Queensland. 

Elizabeth Struhs died on January 7, 2022 at her Rangeville home in Toowoomba after she was allegedly denied medical care for type 1 diabetes for about six days.

The four men and eight women, aged 19 to 64, are expected to be charged with murder later today.

Elizabeth's parents, 50-year-old Jason Struhs and 46-year-old Kerrie Struhs, have already been charged over the girl's death. 

Police said the group was aware of the eight-year-old's medical condition and did not seek medical assistance. 

More than 30 officers conducted a search at a residence in Homestead Avenue, in Harristown, where 12 residents were arrested.

Massive investigation

Detective Acting Superintendent Garry Watts said the investigation was unprecedented.

"And I'm not aware of a similar event in Queensland, let alone Australia."

Detective Watts said the group were expected to be charged tonight and appear in the Toowoomba Magistrates Court on Wednesday.

Sources have told the ABC the religious group is a small and tight-knit group with no ties to any established church in Toowoomba.

Parents charged

Jason and Kerrie Struhs, who are facing charges including murder, torture, and failing to provide necessities of life, were last before the Toowoomba Magistrates Court in late June. 

Appearing via video link the pair again chose to represent themselves.

They were remanded in custody and will return to court later in July.