Prague is on high alert as the swollen river Vltava threatens to break flood barriers and swamp the historic centre of the Czech capital.

Water levels are still rising, but correspondents say the situation is extremely confused and the authorities no longer know what to predict.

The waters are seeping through the makeshift flood defences and bubbling up through the sewers

BBC Prague correspondent Ray Furlong

The emergency services have reopened parts of the Old Town to tourists, suggesting that fears have subsided.

But elsewhere in the city, an embankment was cleared of people as the river started to seep through flood barriers.

Water has also been rising through the sewers, and the basement of the National Theatre has been flooded.

Some of the animals in Prague Zoo have also fallen victim to the floods.

Zoo director Petr Fejk told the Czech news agency CTK that they had been forced to kill an elephant and a hippopotamus which could not be rescued from the rising waters. A gorilla is feared drowned.

Evacuation

In the early hours of Wednesday morning, new areas of the city were evacuated, as the worst floods in over a century failed to abate, despite earlier hopes.

Around the Czech Republic, 200,000 people have been evacuated and 15,000 soldiers and civilians are helping the emergency effort.

The floods have also caused havoc across central and eastern Europe, and around 90 people have been killed across the region.

• In Austria, seven people have died in floods as the River Danube has swollen to record levels. Vienna, Salzburg and much of the Upper and Lower Austria regions are affected.

• In Slovakia, a state of alert was declared as the Danube threatened to flood the capital, Bratislava.

• In Germany, at least six people are reported to have died and another eight are missing in Dresden. A state of emergency has been declared in seven districts of Bavaria and Chancellor Schroeder has promised federal aid to victims of the flood.

• The Black Sea coast of Russia has been particularly hard hit, with at least 58 deaths over the course of the weekend.

Earlier, the level of the Vltava was reported to be within half a metre of flood barriers set up to protect the centre of Prague, with the water rising at about the rate of about 15 centimetres an hour.

Emergency workers are patrolling the streets by canoe

At 0400 (0200 GMT), police and other emergency workers woke people from their beds in the Jewish quarter, Josefov, and several other Old Town districts and ordered them to evacuate.

The city authorities have asked people to take enough food, drink and shelter with them for four to five days.

More than 50,000 Prague residents were evacuated from their homes on Tuesday.

The Vltava is running at 5,000 cubic metres per second - nearly 100 times the summer average.

One point on the river, which usually reaches a depth of one metre, is now up to 7.5 metres.

Nationwide crisis

The floods have already inundated southern parts of the Czech Republic.

At least nine people have died, road and rail lines have been cut, and towns and cities swamped.

The towns of Plzen, Ceske Budejovice - famous centres of Czech beer production - are beginning to recover after being affected earlier in the week.

But the important industrial towns of Usti nad Labem and Mlada Boleslav expect the worst is still to come.

Evacuation orders have been issued for 3,000 people in parts of Luznice na Taborsku and overnight 5,000 people were evacuated from Znojmo na Dyji.

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