Watch: Man attempts floodwater swim to perform rescue as incredible video shows extent of Hawke’s Bay flooding

Incredible video from Hawke’s Bay shows the damage and power Cyclone Gabrielle has unleashed on the region.

Newshub footage shows rapid water streaming down State Highway 50, near Napier Golf Club.

Cars can be seen floating and inundated with water.

The video also shows one man getting into the water and attempting to rescue someone – police officers warned him against the risks of doing so.

Emergency Management Minister Kieran McAnulty has on Tuesday morning declared a national state of emergency.

• Follow Newshub’s live updates on Cyclone Gabrielle

The cyclone has caused buildings to collapse, cut off communities and forced widespread evacuations.

Watch the video.

Newshub.