Police are on the scene as they work to establish what has happened.
A Palmerston North school went into lockdown this afternoon following reports of an incident involving weapons.
"Police are responding to a number of reports of disorder in Longburn, Palmerston North, in which weapons are believed to be involved," a spokesperson said.
There is a police presence in the area and the Armed Offenders Squad has been notified.
"Longburn School has gone into lockdown as a precaution," the spokesperson said.
The school confirmed all staff and students were accounted for.
An employee at the Challenge service station on SH56 said the road was cordoned off and their shop was closed.
A worker at the White Horse Inn said they could see "a lot of police cars" on the road and police all over a nearby property, "just checking everything out".
There were "dozens" of police on the property, he said.
The worker said police had been at the scene for a couple of hours.
He said police had earlier brought someone out of the property.
"I think they just surrendered themselves."
Police announced at 2pm the cordons had been lifted and the school had come out of lockdown.
They have arrested a 35-year-old man on a firearms-related offence.
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