Rain is starting to hit Hawke's Bay as the region bunkers down for a wet night.

The Esk Valley has been evacuated due to concerns around what the extra rain will do to the Esk River.

Hawke's Bay Emergency Management Group Controller Ian Macdonald says rain could cause slips on already soggy land and roads.

He says Police have put cordons in place to protect homes from looters.

MacDonald told Andrew Dickens that it was important to get the evacuation done in day light.

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