CANBERRA, June 6 (Xinhua) -- Australians in areas affected by raging floodwaters have been urged not to cross rivers or enter floodwaters after the body of a 37-year-old man was recovered near Canberra on Monday.

The man is the first person to have been announced as a casualty of the floods, which intensified after storms lashed the east coast of Australia overnight.

Australian Capital Territory (ACT) Police's Station Sergeant Harry Hains told the media the man had attempted to cross the Cotter River near Canberra but became stuck in his car.

While awaiting emergency services support, the man was washed away from his car and his body was found some time later.

"During the course of the (rescue) events a male was located in his vehicle, stuck in raging flood waters in the middle of the Cotter River," Hains told the press on Monday.

"While trying to ascertain a safe method to extract him, the vehicle has shifted and the male has disappeared from view along with his vehicle."

"A search was then undertaken and a short time later, police located what we believe to be a body stuck in raging floodwaters in an island in the middle of the river," he said.

"Police and emergency services declared it was not safe to recover the body last night, this morning, emergency services reconvened and retrieved the body of a 37-year-old male."

Hains, as well as the ACT State Emergency Service (SES), has asked residents not to take unnecessary risks in times of floods as they are unpredictable and help might not always be available.

"What I would like to say is that these types of weather conditions, extreme weather conditions we've experienced, do lead adventure-seeking type people to seek mud with their four-wheel drives," Hains said.

"There is no risk worth taking to cross a flooded river. If a river looks too deep to cross, it's too deep to cross."

The SES's Conrad Barr said floodwaters carried unseen risks, such as stronger currents, felled trees and logs as well as other,  fast-moving debris which could displace cars from the road.

"I can't stress more highly, please don't try to drive through floodwaters, and steer clear of things like storm-water drains and all those sorts of things. I know it might look spectacular but it' s far safer being inside, out of the rain," he told the press.

The storms have caused nationwide power and service outages, with flood warnings extending from Queensland, down through Sydney,  Canberra, eastern Victoria and Tasmania.  Many areas, including the Southern Highlands in New South Wales, have experienced rainfalls of more than half a meter over the weekend.