A police officer has been charged with misconduct and possessing child abuse and bestiality material.

The 38-year-old senior constable, attached to a command in NSW Police’s Northern region, was arrested at about 9am on Tuesday following a months-long investigation.

The probe began in March after reports of unauthorised access to the police computer system.

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In May, investigators seized and forensically examined the officer’s electronic devices.

He has since been charged with misconduct in public office, two counts of possessing child abuse material, one count of possessing bestiality material, and three counts of unauthorised access to restricted police data.

The officer was refused bail and is due to appear in Hornsby Local Court on Tuesday.

He has been suspended with pay, and an urgent review of his employment status is underway.