A teenager has been charged with allegedly threatening someone with an imitation gun inside a NSW shopping centre.

A person was allegedly threatened at a shopping centre in Baylis St, Wagga Wagga, about 3.30pm on Monday.

The teen then allegedly ran off but was found soon after in nearby Morgan St and arrested, police said.

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Police found the gun allegedly used in a unit on the same street.

“The pistol was found to be a plastic toy gun, modified to not display any features distinguishing it as a toy,” NSW Police said.

A 15-year-old boy was charged with possessing an unauthorised firearm and enter enclosed land not prescribed premises without lawful excuse.

He was granted conditional bail to appear before a Children’s Court in July.