"We know from time to time that the message bank on Karlie's phone was accessed. And in response to that, offenders sent some replies to those text messages, confirming that Carlie was alive and well and elsewhere," said Detective Superintendent Des Bray from SA Police.
"We know tragically that some of those SMSs were sent to family members to suggest that Carlie was still alive."
Police say a female pretended to be Karlie in communication with her friends and family in order to get them to send her money and access family benefits payments.
In 2010, they said a woman in a wheelchair went to a bank with identity documents and managed to convince them that she was Karlie.
“All up we believe over $90,000 was transacted through her account,” Det Supt Bray said.