(CNN) Heavy flooding has left at least 18 people dead and more than 280 injured in the northeast region of Brazil, officials say.
The floods have affected nearly 40 cities throughout the state of Bahia, Gov. Rui Costa told reporters in the city of Ilheus, one of the worst-hit.
"This is a massive tragedy. I can't remember seeing anything like this in Bahia's recent history, given the amount of cities and houses involved. It's truly terrifying, there are so many houses and streets that are completely under water," Costa said.
More than 35,000 people have been forced from their homes, according to Bahia's civil defense and protection agency.
The Duas Ilhas dam ruptured in the Brazilian city of Jussiape on Sunday, rising already swollen rivers and flooding surrounding areas.
Jussiape's Mayor Eder Aguiar blamed climate change for the devastation. "We know rain can be seen as a blessing from God but that due to the ecological imbalance that we, human beings, have caused, there can be too much of it, causing serious damage," Aguiar said.
"With great sadness, I was able to witness the rupture of the Duas Ilhas dam, our town's main source of potable water. This caused a sudden level rise of the Contas river, causing streets in our city to become flooded," he added.
Duas Ilhas dam was the second to burst in two days. A dam in the city of Itambé, also in Bahia, ruptured late Saturday.
Brazil's meteorological and natural disaster monitoring agencies warn there is a risk of additional floods and landslides in Bahia, with the possibility of rainfall continuing until at least Tuesday, according to Agencia Brasil.
CNN meteorologist Robert Shackelford says the Brazil National Institute of Meteorology has issued heavy rainfall alerts for nearly all of Bahia. Conditions are expected to improve in the state Monday and Tuesday, he said.
"Widespread rainfall for the next 48 hours is improving slightly, with much of the state seeing up to 50mm, but there are local and isolated areas where up to 100 mm is possible."
Most of the major cities that have been hit by flooding are in their rainy season, so downpours are not unusual, Shackelford said.
"For Itambé, December is their wettest month, which they get about 120 mm of rainfall for the month of December. So they are forecast to get about two-thirds of a month of rainfall throughout this event," he said.