A youth with an airgun sparked a Wellington school lockdown just as children were finishing for the day as armed police swarmed the area nearby.

South Wellington Intermediate School was placed in lockdown amid a police operation just before 3pm.

The school said the lockdown was lifted just after 3.30pm: "Students are being sent home as normal (as per advice from Police)," parents were told in a Facebook post by the school.

Police said the incident was caused by a youth seen with an airgun who was now being spoken to.

In addition to South Wellington Intermediate School several other properties had been placed in lockdown as a precaution, police said.

Earlier, a witness said they have seen "heaps of cops with rifles" at the zoo end of Newtown.

An armed police officer at the scene. Image / Wellington Live

"Police are currently responding to an unconfirmed report of an incident near a school in Berhampore," a police spokesperson told the Herald.

"The school and several neighbouring premises have been locked down as a precaution.

"Members of the public are asked to avoid the Russell Terrace and Rintoul Street area while the incident is resolved."

Wellington Free Ambulance was advised of the incident but did not attend.