Two men accused of sexually abusing children as part of an investigation into "swinging" sex gatherings in Western Australia are now facing a total of 112 charges between them.
Police allege between 2001 and 2006, a 45-year-old man abused his two daughters, who were aged four at the time of the first offence.
He is also accused of abusing his stepdaughter and stepson, who were aged between five and six at the time of the first offence, between 2011 and 2015.
In 2011, he also allegedly sexually assaulted a 14-year-old girl.
The man is now facing a total of 83 charges including indecently dealing with a child, sexual penetration of a child and stupefying.
A 56-year-old man is now facing a total of 29 charges and has been accused of abusing a girl and boy, who were aged five and six at the time of the first offence, between 2011 and 2015.
Both men are scheduled to appear in Perth Magistrates Court on Wednesday.
A woman, who is in a relationship with the 45-year-old man, is accused of abusing her son, eight-year-old daughter and a 14-year-old girl.
The 39-year-old mother was previously charged with a total of 93 offences.
Taskforce Mirzam was launched in February following the discovery of a recording device which contained videos of men and women engaging in sexual acts with the woman's daughter.