BRISBANE, Australia (AP) — Police have charged 19 men in Australia with child sex abuse offenses and rescued 13 children from further harm following tips from the American FBI of an international online criminal network, officials said Tuesday.

Two of the 19 men already were convicted and sentenced to prison terms of almost 15 years in the Australian Capital Territory and five years in New South Wales state, Australian Federal Police Commander Helen Schneider said.

“We will allege that these men were members of a technologically sophisticated online child abuse network that was operating across the country,” Schneider told reporters.

The 19 had been charged with a total 138 offenses related to peer-to-peer sharing of video and images on the dark web. Most were information technology professionals with a high degree of technical competence, she said.

The men, aged 32 to 81, allegedly used software to anonymously share files, chat on message boards and access websites within the network.

Australia-based FBI legal attaché Nitiana Mann said 79 people had been arrested in the United States as part of the same investigation and 43 had been convicted of child abuse offenses.

Schneider said 13 children in Australia had been rescued as a result of the investigation. Police did not detail their circumstances.

The FBI alerted Australian authorities to the network’s existence last year.

Mann said the FBI had alerted other countries to suspects within their jurisdictions but did not name those countries.