The United Nations and other aid agencies were trying to get water and medical supplies to the worst hit towns, UN officials said. But bad weather held up efforts.

The official toll in the Dominican Republic rose Thursday to 339 dead and at least 375 missing, mainly in the devastated town of Jimani. The official toll in Haiti rose by eight overnight to 579 dead.

National Emergency Commission spokesman Jose Luis German said 329 were confirmed dead, 375 missing and 122 injured in Jimani, which was virtually wiped out by the flash floods in the early hours of Monday.

Ten other deaths in the rest of the country have also been blamed on the floods.

German said the toll in the Jimani region would certainly rise as the affected zone was very spread out.

In Haiti, UN relief agencies and non-government groups were trying to fly food, water and medical supplies to the worst hit towns of Mapou Belle-Anse and Fonds Verette.

But bad weather was holding up helicopter flights.

A Geneva spokeswoman for the UN Office for the Coordination of Humanitarian Affairs said a local UN mission, the Red Cross and the Oxfam charity had flown to Mapou Belle-Anse in the southeast with 1.5 tonnes of water and water purification tablets.

A joint World Food Programme and Haitian health ministry team was to go to Fonds Verette, north east of Port-au-Prince, with food supplies, the spokeswoman added.

Two teams of UN disaster experts will leave for Haiti and the Dominican Republic by Friday to help the relief efforts, the OCHA spokeswoman said.

In Haiti, members of the multi-national force brought in to assure security after deposed president Jean Bertrand Aristide resigned and fled at the end of February were also trying to get emergency supplies to the worst-hit areas.

At least 272 people were reported dead in Mapou Belle-Anse and at least 100 in the Grand Gosier area. Another 165 died in Fonds Verettes.

Haiti and the Dominican Republic make up the island of Hispaniola which was hit by 10 days of torrential rains turning rivers into raging torrents. Many of the dead were swept away as they slept in their beds.

In Jimani, many of the people buried in mass graves because of public health concerns were women and children, although families could claim a relative's body.

"The problem is that entire families were lost," he said, "so there's no one to claim them."

More than 32,000 residents have moved out of Jimani, which is 280 kilometers (175 miles) west of Santo Domingo, near border with Haiti. About 210 families lost their homes.

Hundreds of Civil Defense rescuers firefighters and the Red Cross used backhoes and shovels to remove mud covering homes and streets as they looked for survivors, although hopes dimmed on the fourth day after the floods.

Dominican President Hipolito Mejia and US ambassador Hans Hertell examined the devastation. Mejia declared the town a disaster area and a day of national mourning.

The devastation was such that "even the cemetery was destroyed," German said.

Inhabitants of the two countries have told of miraculous survival tales as the Soleil river turned into a torrent in Jimani on Monday.

Bartolina Diaz, 65, said she clung to an iron door on her house that the waters could not drag away, while Dionisio Mendez, 86, who is blind, was swept a kilometer (0.6 mile) downstream before he managed to grab a tree.

The US State Department said the US Agency for International Development had provided 50,000 dollars (41,000 euros) in aid, while the agency's advisors were conducting on-scene assessments for further aid.

TERRA.WIRE