A former Queensland child care worker who allegedly indecently assaulted children and recorded the attacks has been charged with more than 100 offences.
The 39-year-old man is accused of multiple counts of rape, indecent treatment and bestiality, police say.
Detective Senior Sergeant David Miles said some of the assaults happened at a Townsville child care centre.
"But from our understanding at this stage, those appear to have been committed against his own children," he told reporters on Thursday.
The man also "preyed upon" vulnerable women who had young children.
"He has provided them with drugs for the purposes of sedating his victims," Det Snr Sgt Miles said.
Prosecutors will allege the offending took place between 1995 and 2020 and involved 12 victims -- two males and 10 females.
One victim was an adult. The others were aged from 18 months, or less, to 16-years-old.
The man is also accused of sexually assaulting his siblings, making and distributing child exploitation material and supplying dangerous drugs.
Det Snr Sgt Miles said police were working closely with the child care centre to see if more victims could be identified.
"We do know that our main principal target was previously employed at a Townsville child care centre for a number of years," he said.
"We have identified some victims from that particular centre and we're working back through historical records at the moment to identity whether there are any more."
The man is scheduled to appear in Townsville Magistrates Court on September 29.
Police have also charged three other people in relation to the same offences.
Det Snr Sgt Miles said all four offenders live in the Townsville area and communicated through social media to "combine their efforts for committing the alleged offences".
"They were engaged in the trading of child exploitation material between each other," he said.
These include a 33-year-old man accused of six counts of distributing child exploitation material.
The man was also charged with using a carriage service to access child abuse material, producing and possessing dangerous drugs and possessing tainted property.
A 38-year-old woman previously granted bail after appearing in Townsville Magistrates Court for allegedly possessing child exploitation material, distributing child exploitation material and burglary.
A 49-year-old woman has been cautioned on three counts of bestiality involving dogs.
All three are associates of the 39-year-old man and do not work in the child care industry.