Scores of people have been killed and some 42,000 people have been forced to leave their homes in Nicaragua, Honduras, Guatemala and El Salvador.

The authorities in Nicaragua declared a state of emergency in most of the country on Sunday.

Millions of dollars worth of crops across the region have been ruined and outbreaks of malaria, cholera and dengue fever have been reported in some of the worst hit areas.

Remote and impoverished villages have been cut off by the flood waters, power cables have come down and thousands of people are already running out of food and fresh water.

The region, which is still recovering from the effects of last year's Hurricane Mitch, has suffered three weeks of torrential rain, flash floods and mudslides.

Crops ruined

The UN's World Food Programme (WFP) has warned that Central America is facing a food crisis because whole crops of corn, beans, rice and peanuts are likely to be destroyed.

After Hurricane Mitch, which killed 10,000 people at the end of last year, the WFP set up a food distribution network serving around 20,000 people.

That number is now likely to rise significantly, as thousands more leave their homes and move into temporary shelters.

Troops mobilised

Soldiers across Central America are being used to help evacuate people from their homes, in capital cities and in remote areas.

The red alert, announced by Nicaragua's National Emergency Committee on Sunday, mobilises rescue workers, opens refuges and allows the authorities to distribute aid packages.

Honduras declared a maximum state of alert last week after a river burst its banks and swept through the centre of the capital, Tegucigalpa.

In El Salvador, where a state of emergency has also been declared, President Franciso Flores appealed to people who have had to leave their homes not to return until the danger was over.

Guatemalan Defence Minister, Tulio Espinosa, has sent 6,000 troops to the aid of flood victims and the Mexican authorities are on standby to evacuate homes as rivers there are breaking their banks.

New storm

The floodwaters have destroyed two bridges on the Panamanian Highway, making the road impassable and blocking most of Central America's commercial traffic.

The Honduran President, Carlos Flores, has asked the international community for help and financial analysts say the disaster will undermine the region's economy.

The region's water sewage and drainage systems were still blocked with mud from Hurricane Mitch when the latest rains started.