SAO PAULO -- Raging torrents from a ruptured dam swamped a small rural Brazilian city Thursday, killing four people and destroying at least 120 homes in a region already devastated by more than a month of floods. Eleven people were missing, 80 suffered minor injuries and nearly 3,000 were forced from their homes.
Amateur video footage showed water inundating Cocal, population about 25,000, after a section of the dam gave way under the weight of a reservoir bloated by rains.
Floods from those rains have killed nearly 60 and left hundreds of thousands homeless in a wide swath of northern Brazil.
"It was like a tsunami," Gov. Wellington Dias of northeastern Piaui state said after touring the devastation zone.
Some residents climbed trees and scrambled atop rooftops after the floodwaters suddenly swelled a river.
"What I saw was frightening. It was a wall of water 20 meters [65 feet] high, equivalent to a three-story building," Dias said, according to a website operated by SBT television.
Authorities began evacuating families about two hours after the dam failed, but civil defense authorities said Thursday night that 11 people were still missing and that rescue operations had been suspended until Friday. Churches and other buildings were turned into shelters for the 2,953 people who were displaced.
The dead from the dam rupture included girls ages 10 and 12, a 72-year-old man and a 73-year-old woman, the state government said on its website.
Downpours have battered northern and northeastern Brazil since April, causing floods and mudslides in a region extending from the Amazon rain forest to the Atlantic Ocean. Authorities say 59 people have been killed and more than 423,000 were displaced.
Heavy rains in recent days swelled the reservoir behind the dam, increasing pressure that opened a 165-foot (50-meter) tear and eventually led to the rupture, the Piaui state government said in a statement.
"It was a lot of water," resident Antonio Antonino told SBT. "People were desperate, they were crying. I'm 60 years old, and I've never seen anything like this."
The floods also swept away crops and livestock, according to the government statement.
Officials launched an overnight rescue operation using five helicopters to transport victims to safety, and firefighters were sent to aid the victims.
Piaui Civil Defense spokeswoman Vanize Lemos said at least 150 families were initially rescued.
The heavy rains are blamed on an Atlantic Ocean weather system that normally moves away in April but hasn't budged this year. Meanwhile, southern Brazil has been hit by a drought that has severely affected agriculture.
Associated Press Writer Alan Clendenning contributed to this report.