SA man due in court over imitation gun

A man is due to appear in court accused of carrying an imitation firearm in Adelaide's CBD which sparked a high school lockdown.

Adelaide High School was locked down on Monday afternoon after reports of a man walking in the CBD armed with a firearm.

Police, including STAR Group officers, located him about 2.15pm at a housing complex near Light Square.

The 43-year-old will appear in Adelaide Magistrates Court on Tuesday, charged with creating a false belief, carrying an offensive weapon, possessing an imitation firearm without a licence and unlawful possession.

No-one was threatened or injured during the incident and the school was locked down as a precaution.