The Mount Victoria Tunnel in Wellington is closed after a serious two-vehicle crash this afternoon.
Police were called to the crash on State Highway 1 at the Paterson Street end of the tunnel about 4.10pm.
Initial indications suggest at least one person has suffered serious injuries.
The Serious Crash Unit has been notified and is expected to attend the scene. The tunnel is likely to remain closed for some time while emergency services respond and investigations are carried out.
Motorists are being advised to avoid the area and expect significant delays, with traffic diversions in place across the city.
Police have asked drivers to be patient and follow directions from traffic management staff.