Torrential rains lashed Haiti on Tuesday, flooding shanty towns, swamping the squalid camps erected after a 2010 earthquake and killing at least 23 people, officials said.

The worst rains to hit the impoverished country this year -- at the start of the hurricane season -- paralyzed the capital, where most of the deaths took place, according to officials at Haiti's civil protection agency.

Thunderstorms were pounding several north Caribbean islands early Tuesday, but there was little chance of the large low pressure area developing into a hurricane, according to the US-based National Hurricane Center (NHC).

Several days of rain had already swelled rivers, however, and the NHC warned of "flash floods and mudslides over portions of Haiti, the Dominican Republic, Jamaica and Cuba."

Haiti was most at risk of devastation from the wet weather, due to its crumbling infrastructure and ramshackle shelters for tens of thousands left homeless after the catastrophic 7.0 magnitude earthquake in January 2010.

Health officials here also fear an uptick in fatalities from a cholera outbreak that erupted last October. The diarrheal illness thrives in crowded areas where people rely on contaminated water.

The death toll in Haiti included two people who died as waters rose in the tent camp near the ruined presidential palace and two children who were buried when their home collapsed, officials said.

Nadia Lochard, from the civil protection agency, said 13 people were killed in the upscale suburb of Petionville, "most when their houses collapsed or were swept away in mudslides."

Newly elected President Michel Martelly headed to the city's poorest neighborhood, Cite Soleil, which officials said was completely swamped by the rainfall and where people sought higher ground on the roofs of their homes.

"I was in the streets during the rain, and I got home, put my boots on, and I'm back in the streets to assess the situation," Martelly said in remarks broadcast on national television.

"I'm now trying to help people and distribute some food. I hope people can find shelter," said Martelly, who handed out supplies with members of his new cabinet.

The rains brought the city to a standstill, with waters coursing through the streets and cars jammed up in long lines, some abandoned by their owners. The floodwater was reportedly four feet (1.2 meters) deep in some camps.

The rain let up during the day, but the forecast called for another downpour overnight and into Wednesday, raising fears that mud slides could sweep away entire camps perched on the bare slopes around larger cities.