The case against the men - Timothy Luke Doyle, 26 and Steven Garrad, 21 - was heard before the Port Macquarie Local Court on September 10, where the matter was adjourned until October 22.

The men were arrested in June 2020 as part of Operation Arkstone, which was launched in early 2020 after a tip-off from the United States' National Centre for Missing and Exploited Children to the AFP's Australian Centre to Counter Child Exploitation (ACCCE).

On June 4, 2020, investigators from the Australian Federal Police (AFP) Eastern Command Child Protection Operations and the New South Wales Police Force Child Abuse and Sex Crimes Squad and Mid North Coast Police Area Command executed search warrants at premises in the towns of Kendall and Old Bar.

Both men were refused bail and remanded in custody following an appearance before the Kempsey Local Court on June 5, 2020.

The men will now face an additional 190 and 53 state and Commonwealth charges respectively in relation to various child abuse, child abuse material and adult sexual assault matters.

Both men face a potential maximum penalty of life imprisonment.

AFP Eastern Command Detective Superintendent Ben McQuillan said the additional charges show that police investigations can continue long after initial arrests are made.

"While our first priority is to act quickly to remove children from harm, our investigations continue to uncover the extent of alleged offending and put this evidence before the courts," Detective Superintendent McQuillan said.

Detective Acting Superintendent Chris Goddard, NSW Police State Crime Command's Child Abuse and Sex Crimes Squad Commander said while getting those who may endanger the community off the streets is important, so too is ensuring they are held accountable to all the crimes they are alleged to have committed.

"Along with our partnering agencies, NSW Police will do everything within our scope to ensure that all victims of heinous crimes such as these are delivered the justice they deserve."

The AFP have been working with the ACCCE and state police in NSW, Queensland and Western Australia on the investigation. Investigations remain ongoing and further arrests and charges have not been ruled out.

NSW Police has confirmed the arrests are in no way related to the investigation into the disappearance of William Tyrrell.

Members of the public who have any information about people involved in child abuse and exploitation are urged to call Crime Stoppers on 1800 333 000.

You can also make a report online by alerting the Australian Centre to Counter Child Exploitation via the Report Abuse button at www.accce.gov.au/report.

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