The death toll from flash floods and mudslides in Rio de Janeiro's picturesque Serrana region reached 702 on Tuesday, a number that is likely to rise further in one of Brazil's worst natural disasters on record.

Firefighters react during a mass in tribute to the victims of landslide in Nova Friburgo January 18, 2011. [Agencies]

Authorities say many residents in the region are still missing - some believed to be buried. Hundreds of people are still in areas at risk of fresh mudslides, some cut off from help by washed out roads and bridges while others refuse to leave for fear their houses will be looted.?

The death toll is still rising daily as rescuers dig out more bodies from the wreckage. Authorities have ventured no estimates of the number of missing, but local papers estimated on Monday over 100 people are unaccounted for.

Rains let up during the day on Tuesday in the disaster-hit areas but picked up again in southeast Brazil on Tuesday evening.

Army helicopters have been carrying out rescue and supply operations to attend to residents cut off from help for nearly a week since rains unleashed a sudden spate of hillside mud, trees and boulders on the tourist towns below, sweeping away or burying neighborhoods.

In the hilly resort region north of Rio de Janeiro city, Nova Friburgo has registered the greatest number of deaths with 335, followed by Teresopolis with 285.

"We are advising people who live in areas of the highest risk to leave their homes," Rubens Placido of the Nova Friburgo Fire Department said. "There are people that don't want to leave, so we are checking with the courts if we can obtain support from the police force."

Populist politics and lack of urban planning across much of Brazil has allowed the construction of whole neighborhoods in areas with high risk of flooding and mudslides.

The federal government has earmarked 780 million reais ($463.5 million) in emergency aid for the region.

On Tuesday, President Dilma Rousseff met with World Bank officials who said they were working out the final details on a $485 million emergency relief loan to the state of Rio de Janeiro for the disaster hit areas.

"We hope the first tranche of the loan, $290 million, can be approved in the coming weeks," said Makhtar Diop, director of the World Bank for Brazil.