A massive cleanup was underway on Australia's east coast on Saturday after a severe storm killed as many as eight people and caused widespread damage.

Hundreds were forced out of their homes in New South Wales state, and more than 200,000 houses and businesses were without power. State officials described it as the worst storm in three decades.

A washed-out section of road is seen on the New South Wales coast, 80 kilometres north of Sydney.
(Mark Baker/Associated Press)

The bodies of a man and two children were discovered in an area where police were searching for a family of five who went missing when their car fell into a swollen creek after a section of highway collapsed near Gosford. Authorities feared another child and the man's wife did not survive.

Elsewhere, police recovered the bodies of a couple whose car was swept off a bridge near the city of Newcastle.

In a separate incident, a Newcastle man is believed to have drowned after floodwaters swept him into a storm drain.

Gale-force winds uprooted trees while heavy rains washed away the soil beneath highways. The rushing water from flash flooding was powerful enough to drag away a number of cars.

Flooding was reported on some Sydney roads, and flights in and out of the city were delayed.

During the storm, a cargo ship ran aground on a Newcastle beach. The crew of an Australian Maritime Safety Authority aircraft later found no sign of pollutants leaking from the ship carrying more than 700 tonnes of fuel.