UPDATED 12.37pm Cordons have been lifted and a high school's out of lock-down following an alleged armed incident in Napier.

Police have reopened a section of Onekawa bordering William Colenso College, which was briefly put into lock-down.

Armed officers closed off Riverbend Road at about 9.30 this morning, while armed offenders squad officers went into the area.

As a precaution William Colenso College students were kept within the grounds.

Police say the incident is now over.

It was not yet known what the incident involved although it is understood a threat had been made and the person involved may have indicated they had a firearm.

A police representative said the parties involved were known to each other.

One resident nearby said the police arrived "silently" and without a fuss.

He had seen armed officers walking into the closed off area looking in properties.

Police were also checking boots of vehicles of residents who live within the closed off zone and were driving out.

A status posted on the school's facebook page earlier this morning stated they were currently in lockdown.

"We are currently in a lockdown situation, we are working closely with the police," it read.

"All students and staff are safely locked in at school. Please do not come into school until further notice. We will keep you informed. Further information can be found at the Eastern District Police Facebook site."

As of 11am, there were no posts on the Eastern District Police Facebook site.