Emergency officials from across the coast said the toll could climb to 11 or higher as other deaths recorded during the flooding are evaluated to see whether they had been caused by the storms.

In one of the hardest hit areas in eastern Pennsylvania, county officials ordered the evacuation of up to 200,000 people from low-lying areas around the Susquehanna River amid fears that the river would spill over the dykes as waters crest.

Evacuation efforts stretched from Virginia -- which declared a state-wide emergency -- to New York as up to a foot (40 centimeters) of rain fell through parts of the region and forced residents to rooftops in scenes reminiscent of last year's Katrina disaster.

"We were afraid of a New Orleans-type situation where we just couldn't get people out," said Pennsylvania Governor Ed Rendell said.

A state of emergency was declared in 46 Pennsylvania counties and Rendell said helicopters had already been brought in to fly search and rescue missions, plucking stranded residents from their rooftops.

"The next 12 to 14 hours will tell whether this is a full-scale disaster," Rendell told CNN.

New York Governor George Pataki said he would ask the federal government to declare a state of emergency for his state and warned that he was bracing for the worst because waters had not yet crested.

"We have never seen a natural disaster this bad in the state of New York," Pataki told CNN.

"It's not over," Pataki cautioned. "We know that a part of the rivers in the state have not crested."

The mayor of Washington, D.C,. also declared a state of emergency of the US capital.

Meanwhile coast guard officials across the east coast urged residents to carefully follow evacuation warnings as water continued to rise.

"We're hoping that people heed officials' warning and get out of the way" of the floods, David McBride of the Virginia Coast Guard told the television station.

The fatalities from the regional floods included three dead in Maryland, three in New York state and one in Pennsylvania.