Army General Hernan Olmos, who is heading up rescue efforts, told reporters that three children and one adult had been killed in the floods.

Officials said a fifth person was killed Tuesday night in neighboring Entre Rios province, when he drowned in the swelled river.

Earlier tolls listed two dead, noting that thousands had fled their homes in Santa Fe and Entre Rios amid the flooding, caused by torrential rains.

One-third of Santa Fe province -- Argentina's third-largest, with some 2.9 million residents -- is "underwater," provincial Governor Carlos Reutemann told reporters.

Farmers' losses in the agriculturally rich region known for its soya and cattle were estimated at more than 200 million dollars and many local families had to spent the night in area schools and government buildings.

The floods have wiped out at least one bridge, cut the water and power supply to many homes and virtually shut off access to the city from local highways, according to local officials.

In the Centenario district of modest, one-storey homes, muddy waters reached halfway up the front doors. Hundreds tried to salvage their modest possessions by ferrying them away in makeshift boats, rafts and kayaks.

One man in water up to his neck was seen here, pushing along a door serving as a raft for a sleeping dog, while others were afraid to abandon their homes, fearing looters.

"It's a national catastrophe," Duhalde said. "But not a single province will be left by the government to its own devices," he vowed.

Reutemann, a onetime Formula 1 race car driver, said the floods were the worst in the history of the city of some 400,000, which was founded by Spain in 1573.

And he predicted that matters would get even worse in the coming hours.

"My intuition tells me that the water could still rise several centimeters (inches) today," he said.

Weather forecasts late Tuesday seemed to back up Reutemann's prediction, noting that more rain was expected in the next 48 hours and was likely to "aggravate the situation in the region."

Waters in the Salado River, which runs through the city, hit the eight-meter (26-foot) mark, exceeding the previous record of 7.19 metersfeet).

Duhalde planned to call an emergency meeting to discuss the situation.

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