Mersane Warria, 37, did not attend the brief hearing at Cairns Magistrates’ Court on Monday as she remains in hospital under police guard being treated for stab wounds to the chest.

Police are still investigating how the four girls and four boys – aged between two and 14  – died at the house in the Cairns suburb of Manoora on Friday morning. They have already confirmed that some of the children had suffered stab wounds, and officers are examining several knives found at the house. However, Detective Inspector Bruno Asnicar said on Sunday that suffocation was also among the possible causes of death.

“We are considering that and that’s why it’s taking a bit of time,” said Det Insp Asnicar, quoted by the Associated Press. “It could be a range of things, from suffocation to a thousand other things.”

During the court hearing magistrate Alan Comans rejected a request from Warria’s lawyer to hold the next hearing in a mental heath court. Warria was remanded in custody and the case adjourned until January 30.

Meanwhile it has emerged that the house where the children were found dead by an older brother is likely to be demolished, and replaced with a permanent public memorial.