Landslides triggered by heavy rains have killed 13 people over the past 24 hours in the Brazilian tourist town of Petropolis, an official said Monday.

"We are in a state of maximum alert," Rio state governor Sergio Cabral told a news conference in Petropolis, a former imperial capital located 68 kilometers (42 miles) north of Rio de Janeiro, as he updated the death toll from 10.

He urged residents to leave high risk areas and to seek refuge in shelters provided by city authorities amid worsening downpours.

Brazilian President Dilma Rousseff, in Rome to attend Tuesday's installment of Pope Francis, called Cabral to offer federal help to deal with the impact of the flooding, her office said.

Among the victims are two civil defense officials who took part in rescue efforts, Sergio Simoes, the Rio state civil defense secretary, told Globo television earlier.

Simoes described the situation in the town, where emperor Pedro II and his court used to spend the summer, as "very serious."

"The continuing rains heighten the risks of mudslides. There are many vulnerable areas in the mountainous region and as a result we are very concerned," he said.

Up to 390 millimeters (15 inches) of rain have fallen in some city districts in the past 24 hours, when only 270 millimeters were anticipated for all of March.

Petropolis Mayor Rubens Bomtempo urged residents to remain indoors and warned of the possibility of more landslides.

A civil defense statement said the rains also affected other Rio state towns, including Angra dos Reis, Mangaratiba, Niteroi and Teresopolis.

In January 2011, more than 900 people died in Rio state's rugged region after heavy downpours spawned flooding and landslides.