WARNING: GRAPHIC CONTENT

The former partner of alleged child sex trafficker Peter Scully, accused of torturing children in the Philippines for “dark web” videos, has been arrested following a year-long investigation.

The Melbourne man allegedly filmed the despicable sex crimes, some committed against an 18-month-old baby, and sold the sex videos for up to $10,000 to European and American buyers.

The worst of the videos, dubbed Daisy's Destruction, allegedly showed an 18-month-old baby girl tied upside down by her feet, sexually assaulted and bashed by two of Scully's masked and naked Filipino girlfriends.

View photos Liezyl Margallo is believed to be the masked and naked woman who appears in the confronting video Daisy's Destruction, where a baby girl is raped and tortured. Pictures: NBI/Interpol More

The content in the video is so horrific, top investigators in the Philippines were brought to tears.

Scully was arrested last year in the Philippine city of Malaybalay and has pleaded not guilty to charges of rape and trafficking.

Liezyl Margallo, 23, a former prostitute, is expected to testify in court against the 52-year-old, who fled Australia in 2011 after being wanted for fraud and started a new life in the Philippines.

She was allowed to go free during Scully’s 2015 arrest because investigators including local police, and Australian Federal Police, did not have sufficient evidence against her, The Sydney Morning Herald reported.

View photos Liezyl Margallo had a Facebook account going by the name 'Shannon Carpio', which has since been deactivated. Picture: Facebook More

View photos Melbourne man Peter Gerald Scully walks in handcuffs as he arrives at Cagayan de Oro city in June, 2015. Photo: AAP More

After more than 12 months of investigations, Margallo is now behind bars after evidence emerged revealing her as the masked and naked woman who appeared in the confronting video Daisy's Destruction.

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