UPDATED 2.46pm: The 32 year old man arrested after trying to enter the Linwood Work and Income office with a gun has made a brief appearance in the Christchurch District Court.

Mitchell Moulton is charged with discharging a pistol in a public place, possession of a pistol and possession of a cannabis plant.

He's been remanded in custody without plea.

He was spotted carrying a firearm outside the Linwood office on Aldwins Road shortly before 8.45.

Superintendent John Price said the man failed to gain entry to the office and fled the scene in a vehicle.

He says police and AOS stopped the man about 9.15 on Ferry Road.

He was arrested after a short foot chase.

The Linwood WINZ office will remain closed while police speak to staff.

All other WINZ offices were placed in lockdown but have now reopened.

Public Service Association national secretary Richard Wagstaff said this sort of threat is completely unacceptable.

"It's shocking, it's deplorable, I think all New Zealanders would be pretty upset to hear of anyone facing this at work. There really needs to be a change in attitude."