Police catch man in online sting

Police posing as a teenager have arrested a 38-year-old Christchurch man in an online sting.

Mathew James Momo, 38, allegedly sent indecent messages and explicit photos to both a person aged under 16 and a constable pretending to be under 16.

But for operational reasons, police won't disclose how it investigates online child exploitation cases.

Momo appeared in the Christchurch District Court on Monday, facing two charges, one intentionally exposing a minor to indecent material and one of intentionally exposing a constable pretending to be a person under 16 years to indecent material.

He is next expected to appear in the district court on November 22.