Landslides caused by heavy rains killed nearly 30 people in the metropolitan region of Recife, the capital of northeastern Pernambuco state, authorities said.
“In the last 24 hours, 28 deaths have been recorded,” the Civil Defence said in a statement on Saturday.
More than 760 people have been forced to leave their homes because of the flooding in Pernambuco, civil defence officials said on Twitter.
The executive secretary of the civil defence agency in Pernambuco, Lieutenant Colonel Leonardo Rodrigues, said in a video posted on Instagram that about 32,000 families live in areas at risk of landslides or flooding in the state.
Schools in the city of Recife have been opened to receive the homeless.
In Alagoas, another state in the region, two people died when they were swept away in river flooding on Friday.
In Alagoas, the state government said 33 municipalities have declared an emergency due to the effects of the heavy rains in the past several days.
Videos posted on social media show wide flooded avenues in several municipalities, collapsing houses and landslides.
Between Friday night and Saturday morning, the volume of rainfall reached 236 millimetres (nine inches) in some parts of the Pernambuco capital, according to the mayor’s office.
That’s equivalent to more than 70 percent of the forecast for the whole month of May in the city.
The Pernambuco Water and Climate Agency said the situation could worsen as rain will continue for the next 24 hours in the state.