South Australia's child protection minister says it would be "appalling" if men were banned from looking after children after a carer was accused of horrific child sex abuse.

A 32-year-old Adelaide man employed by Families SA has been charged with unlawful sexual intercourse with seven young children under his watch at a residential care facility.





Police have warned there are likely to be more victims identified as investigations continue.

And Premier Jay Weatherill has warned South Australians to brace for the worst when details emerge of the alleged offences, saying they could amount to "one of the most catastrophic events in Australian history".

The accused man, whose name has been suppressed, was also charged with the production, possession and dissemination of child exploitation material after police found more than 100,000 still images and 600 video files.

The premier has flagged a royal commission into the sexual abuse of children, and foreshadowed "radical changes" to child protection protocols.

He told ABC Radio on Wednesday that everything was on the table, including a suggestion for female-only carers despite his personal reservations.

Child Protection Minister Jennifer Rankine said it would be a big call to exclude men from contact with children.

"We have great men in our system, great men in (SA Police) and great men in this department, whose every working minute is aimed at keeping children safe," she told reporters.

"I'm the mother of two adult sons and I couldn't be prouder of my boys. I think it would be just the most appalling thing to say little children no longer have contact with men."

Ms Rankine confirmed on Wednesday that four of the seven victims identified by police remained in state care.

The other children were reunited with their families before police discovered the alleged crimes.

Family First MLC Dennis Hood has called on the government to ensure carers are not left alone with children but Ms Rankine said it would be virtually impossible to ensure this.

"What we're talking about here is over 300 children on any given day in residential care (and) those children all have different activities that they undertake," she said.

"To have two workers with every child at every point during the day is just impractical. I don't know if there is any system that could actually accommodate that."