Five people were confirmed killed on Friday in record flooding in northern New South Wales with 50,000 people cut off, thousands of homes and businesses without power and cattle herds wiped out.

Officials in Australia's most populous state made a natural disaster declaration in response to record rainfall.

Four people have died and several were missing as major flooding in New South Wales (NSW) left about 50,000 people isolated by floodwaters. The record rainfall, now declared a natural disaster, has been caused by a slow-moving area of low pressure and is greater than any in living memory for some residents, according to local authorities.