UPDATED 7.56am: Air New Zealand say a plane at the centre of a security scare is now able to be boarded again.

Police say people were ordered off a plane at Auckland Airport because of a threatening text received by a passenger.

Flight 501 was scheduled to fly from Auckland to Christchurch.

Labour MP Jacinda Ardern was on board and tweeted that the pilot told everyone to get off.

She said all passengers did just that, and police, security staff and security dogs are now there.

Police then checked the plane for suspicious devices.

Seems our plane has some kind of security situation. All passengers pulled off and police, security and dog all onboard now

— Jacinda Ardern (@jacindaardern) November 22, 2016

Labour MP Peeni Henare was among those on Flight 501.

"I think the plane was almost ready to depart and it looked like the doors were about to be closed,.

"A very polite and calm voice came over the intercom saying 'please evacuate the plane and take all your luggage'," he said.

Mr Henare said passengers looked at each other curiously, but were told it was standard procedure for a risk of this nature.

"At least two sniffer dogs, several police and a swag of security staff... it was rather calm, it wasn't rushed or anything but just a heck of a lot of people."

Mr Henare said it's the first time an incident like this has happened in his two years as an MP.