By Jason Hovet and Jana Mlcochova
PRAGUE (Reuters) - Volunteers piled up sandbags to keep a swollen river from overwhelming the Czech capital's historic center on Monday after floods across central Europe forced factories to close, drove thousands from their homes and killed at least six people.
Five people were killed at the weekend in the Czech Republic, where the flooding was the worst in a decade, while in Austria one clean-up worker was killed in a mud-slide near Salzburg and another three people were missing.
The flooding, which also affected parts of Germany, Slovakia, Hungary and Poland, sent shares in reinsurers Munich Re and Hannover Re down by about 3.5 percent with markets anticipating big claims from property owners once the waters recede.
Carmaker Volkswagen temporarily shut its plant in Zwickau, in the eastern German state of Saxony, because the flooding stopped workers reaching the factory, and parts of the German town of Passau, at the confluence of the Danube and two other rivers, were flooded.
The last time central Europe saw similar floods was in 2002, when 17 people were killed in the Czech Republic, and damage estimated at 20 billion euros ($26 billion) was inflicted.
Officials in Prague, the Czech capital listed by the U.N. cultural agency as a World Heritage Site, said they did not anticipate the waters of the swollen Vltava river, which runs through the center, would reach the 2002 levels.
But they were not taking chances. They shut the metro system and, in streets near the river, soldiers put up mobile metal fences - flood defenses that were ordered after the disaster 11 years ago. Elsewhere, volunteers built walls of sandbags.
The Charles Bridge, a favorite spot for tourists which dates back to the 14th century, was closed. Tree trunks floated by in the muddy brown water. A riverside path, which is below street level, is usually populated with cyclists and people sitting at cafes, but it was under water on Monday.
"We left England yesterday and it was sunny and warm. We didn't expect this, we don't even have our raincoats," said British tourist Alison Tadman, who came to Prague with her husband, Adrian, to celebrate her 47th birthday.
She and her husband were sheltering in a McDonald's restaurant. "We're pretty disappointed," she said.
Some of the worst flooding was around the Danube river, which starts in Germany and snakes its way through countries including Austria, Slovakia and Hungary on its way to the Black Sea. The river was swollen by heavy rain at the weekend.
In Germany, the interior minister flew to the flood-hit regions on Monday and Chancellor Angela Merkel was preparing to go on Tuesday, government spokesman Steffen Seibert said.
How her government responds to the emergency could influence the outcome of a nationwide election in September. "It's perfectly normal the leader of the government would go to the region and see what is happening for herself," said Seibert.
Shipping was stopped on parts of the Danube and Rhine rivers in Germany - both important arteries for shipping grains, coals and other commodities - because of the high waters.
Thousands of people living in low-lying areas in Austria, and the Czech Republic, had to be evacuated from their homes. Czech Prime Minister Petr Necas declared a state of emergency on Sunday for most of his country.
The risk on Monday was that the flood danger could follow the course of the Danube river downstream to other European countries along its route.
In Hungary, whose the capital Budapest is built on the banks of the Danube, state media quoted Gyorgy Bakondi, head of the National Disaster Authority, as saying that 400 people were working on flood defenses.
He said water levels in the river could reach or even exceed the height seen in the record flooding in 2002.
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(Reporting by Robert Muller, Jan Lopatka and Michael Kahn in Prague, Georgina Prodhan in Vienna, Erik Kirschbaum in Vienna, Jonathan Gould in Frankfurt, and Gergely Szakacs in Budapest; Writing by Christian Lowe in Warsaw; Editing by Pravin Char)