The death toll caused by record rainfall in southeastern Brazil jumped to at least on 44 on Sunday as officials expressed alarm about continuing storms.

At least 44 people had died in the state of state of Minas Gerais. There were also reports that nine others died in neighbouring Espirito Santo. More than a dozen people remained missing, authorities said.

Some 20,000 people had been evacuated due to the threat of floods and landslides.

The capital of Minas Gerais state, Belo Horizonte, recorded 171mm (6.7 inches) in a 24-hour period from Thursday to Friday - the highest rainfall in 110 years.

State Governor Gustavo Zema declared a state of emergency in 99 cities, a measure meant to facilitate federal disaster aid.

View of damage after a landslide in Vila Bernadete, Belo Horizonte, Minas Gerais state, Brazil [Douglas Magno/AFP]

He also decreed three days of official mourning for those killed in the floods and landslides.

Authorities in Espirito Santo said they were on maximum alert" due to a forecast for more rain.

In the city of Alegre, officials warned that a dam was in danger of breaking and urged people living below to evacuate.

Another 2,000 people were evacuated in the Rio de Janeiro state city of Itaperuna.

From India, where he is on an official trip, President Jair Bolsonaro said the government was doing "everything possible," while adding that in such a large area "it is difficult to serve everyone".