Record breaking floods in Brazil have left thousands homeless, with people having to be rescued from their roofs by the military.

Footage showed residents hit by downpours receiving help as the country faced its worst flooding in 80 years.

Local authorities in Brazil's southernmost state of Rio Grande do Sul said that floods had so far claimed 56 lives as of Saturday afternoon, with dozens still yet to be accounted for.

Rio Grande do Sul's civil defense authority said 67 people were still missing and more than 32,000 had been displaced as storms have affected nearly two thirds of the 497 cities in the state, which borders Uruguay and Argentina.

Floods destroyed roads and bridges in several regions of the state. The storm also triggered landslides and the partial collapse of a dam at a small hydroelectric power plant. A second dam in the city of Bento Goncalves is also at risk of collapsing, authorities said.

Extreme floods in Brazil have left some people waiting to be rescued from their roofs by the military after their  homes became submerged in water

Footage showed residents being assisted out of their flooded homes through the roof 

A total of 56 Brazilians have died so far in the country's worst floods in 80 years

A street left underwater by the heavy rain in Porto Alegre, a city in the Rio da Grande do Sul state

At least 56 are dead and 67  left unaccounted as of Saturday afternoon for following the intense flooding

A car makes its way through a flooded street in Porto Alegre

Over 32,000 people have been left displaced by storms which have affected two thirds of Brazilian cities

A fruit vendor tries to save his products from flooding and his stall is surrounded by water

In Porto Alegre, the capital of Rio Grande do Sul, the Guaiba lake broke its banks, flooding streets.

Porto Alegre's international airport has suspended all flights for an indefinite period.

Rain is expected in the northern and northeastern regions of the state in the next 36 hours, but the volume of precipitation has been declining, and should be well below the peak seen earlier in the week, according to the state meteorology authority.

Still, 'rivers water levels should stay high for some days', Governor Eduardo Leite said on Saturday in a live video on his social media, adding it was difficult to say for how long.

Less intense rain is expected to continue over the next 36 hours, with precipitation expected to have peaked

Pictured: An aerial view shows the scale of widespread flooding in Porto Alegre

Rio Grande do Sul is at a geographical meeting point between tropical and polar atmospheres, with climate change among factors believed to be behind the extreme weather

Another flooded street in Porto Alegre. River water levels are expected to remain high for days

Rubbish bins bobbing in a flooded street, as the high water level forces a pedestrian to roll up his trousers

Rio Grande do Sul is at a geographical meeting point between tropical and polar atmospheres, which has created a weather pattern with periods of intense rains and others of drought.

Local scientists believe climate change is among factors contributing to the intensifying weather pattern.

Heavy rains had already hit Rio Grande do Sul last September, as an extratropical cyclone caused floods that killed more than 50 people.

That came after more than two years of a persistent drought due to the La Nina phenomenon, with only scarce showers.