Two teenagers from Moree, New South Wales, have been charged in connection with a terror probe after a 15-year-old and a 16-year-old were found to have accessed and possessed extremist material online.

The charges allege the 15-year-old knowingly collected and made documents connected with terrorism and used a carriage service to transmit violent extremist material, while the 16-year-old is charged with using a carriage service to possess violent extremist material.

The investigation is being led by a NSW joint counterterrorism team that includes the NSW Police, the Australian Federal Police, the Australian Security Intelligence Organisation, and the NSW Crime Commission.

The charges followed a joint NSW and federal counterterrorism probe triggered by a forensic examination of items seized in the week prior during a search warrant.

Prosecutors say the seized documents and materials reportedly provided instruction on committing mass casualty events, including knife attacks.

Both teens have been refused bail and will appear before Parramatta Children’s Court on a date to be scheduled.

Authorities conducted two searches of Moree residences, seizing handwritten notes, extremist literature, a ballistic-style vest, notebooks, and a mobile phone.

One of the searches on March 27 resulted in the 15-year-old being charged, with ongoing investigations into additional seized items and their relevance.

The NSW Joint Counter Terrorism Team conducted multiple raids and analyzed items seized from two homes in Moree as part of the probe.

The current case follows another NSW incident in which a Sydney inner-west 16-year-old allegedly downloaded extremist manuals detailing mass casualty attacks and began planning a terror act.