New Zealand has declared a state of emergency in its capital city Wellington as torrential rain and flash flooding drenched the country's North Island.

Footage online shows vehicles submerged, trees uprooted and houses hit by landslides. Wellington received a record 77mm (3in) of rain in less than an hour on Monday, said mayor Andrew Little.

Local authorities advised residents to hunker down, with rain forecast for the next day and a half. Some flights at Wellington Airport have been cancelled and several schools have shut their campuses.

More than a dozen people have been evacuated while a 60-year-old man in the Karori suburb has been reported missing. No fatalities have been reported so far.

This series of flash floods comes less than a week after Cyclone Vaianu swept through the North Island last weekend.