PORT-AU-PRINCE, Haiti - Heavy rain hammered southern Haiti for a seventh straight day Tuesday, triggering floods and mudslides and causing houses and shanties in the capital to collapse. The official death toll was 23 but could rise as remnants of the storm lingered.

Haitian authorities listed six people as missing.

Runoff from the rain sent rivers surging and flooded many homes as people scrambled to their rooftops. The slow-moving storm system also toppled trees and debris blocked streets throughout the capital.

At least 23 people were killed and more than a dozen injured, said Edgar Joseph, a spokesman for Haiti's Civil Protection Department. Most of the deaths were in Port-au-Prince and they included two who died over the weekend, he said.

Thirteen people died in Petionville, a hillside city southeast of downtown Port-au-Prince, Joseph said. In one incident, a concrete house slid down a ravine and crashed into several smaller homes.

A 53-year-old man, Jean Wildor Charutis, said his older sister and a niece died in the large house that crashed down the ravine. "There was so much rain it shook the house," he said as he and government rescue workers searched for survivors.

The storm system has saturated much of the Caribbean in recent days, with flooding reported in the neighboring Dominican Republic as well as in Jamaica, Puerto Rico and the U.S. Virgin Islands. Authorities reported two deaths in the Dominican Republic and one in Jamaica to the weather.

Civil defense authorities in the Dominican Republic said 25 homes were destroyed and more than 8,400 people were evacuated. The dead included a 13-year-old boy who was swept away and drowned while watching a river swell near Santo Domingo.

In Haiti, the week of pounding rain has deepened the misery for tens of thousands of people living in the tent-and-tarp settlements that sprung up after the January 2010 earthquake. Aid groups have warned that the wet weather could worsen a cholera outbreak that has killed more than 5,300 people since October.

Michel Davison, a coordinator for the International Desk of the U.S. National Oceanographic and Atmospheric Administration, said satellite data indicate that rain drenched Haiti along the border with the Dominican Republic for at least six hours Monday night, dumping between four to six inches.

"That's a fairly intense rainfall amount," Davison said in a phone interview. "That's been happening now for five, seven days. The ground is so saturated at this point that it doesn't take much to produce floods."

Davison said Haiti will see more rain Wednesday, but should get a much-needed reprieve later the week.

Two children died and three others were injured in the Nazon neighborhood in Port-au-Prince after the wall of a home fell on them, according to the Civil Protection Department.

Meanwhile, hospitals saw an influx of patients.

Doctors at a hospital run by the Miami aid group Project Medishare treated at least 10 people for injuries, including a puncture wound, said Gabriele Denis, a hospital administrator. Aid group Doctors Without Borders treated at least 10 people, many of them injured when walls fell on them, said Sylvain Groulx, chief of mission for Doctors Without Borders.

Haiti's newly elected President Michel Martelly took to national television just before midnight to calm the nation as the storm was still passing over the city. "This message is to tell the population that I'm with you," the president said.

Martelly ordered government construction workers to show up to work early Tuesday to help remove debris.

Rains earlier this week prompted the government and international aid groups to evacuate dozens of families who live around the overflowing Lake Azuei.