SANTIAGO, Dominican Republic - Dominican authorities reported 11 more deaths yesterday from Tropical Storm Olga, raising to 25 the death toll across the Caribbean from the second devastating storm to hit the island of Hispaniola in two months.

The vast majority were killed in the central Dominican province of Santiago after officials, fearing the collapse of a dam, ordered the release of billions of gallons of water into the Yaque River and inundated seven towns along the waterway's path.

"We knew the damage we were going to cause below," said Octavio Rodriguez, a member of the committee that decided to open the floodgates. "We did not want to, but we had to."

Furious residents said they were warned just minutes before huge waves came crashing down the river, sending plumes of mud careening into houses.

"They warned us, but there was no time," said Sonia Duran Maldonado, 50.

Officials explained Wednesday that as heavy rains overwhelmed the Tavera Dam near Santiago, the country's second-largest city, they decided to release water to prevent an outright collapse.

As of yesterday, at least 19 fatalities were confirmed in Santiago province and three more elsewhere in the Dominican Republic. The storm displaced 34,000 people, emergency officials said.

In Haiti, an elderly woman and a 3-year-old boy were killed. In Puerto Rico, a rain-triggered avalanche buried an SUV, killing a passenger.

Olga was just the 10th named storm to develop in the month of December since record-keeping began in 1851, according to the National Hurricane Center in Miami. It struck the Dominican Republic six weeks after Tropical Storm Noel left 87 dead on its way to becoming the deadliest storm of the 2007 Atlantic hurricane season.

Since Oct. 1, at least 214 have been killed by floods and landslides on Hispaniola, the island shared by the Dominican Republic and Haiti.