Rising flood waters have forced thousands to leave their homes in the southern Czech Republic, with warnings that other areas are under threat.
Barriers are being erected in Prague to protect historic areas
The capital, Prague, is braced for floods, reinforcing barriers on the banks of the Vltava river.
The Vltava, which like the Dyje and Elbe rivers has risen because of heavy rain and melting snow, flooded the city centre in 2002, killing at least 16.
People living in the German states of Bavaria and Saxony are also on alert.
The Czech cabinet has called an emergency meeting for Thursday to discuss the situation and Prime Minister Jiri Paroubek is cutting short a trip to Egypt to return home.
Other measures being taken have included halting production at the Spolana chemical factory on the Elbe in Neratovice, 30km (18 miles) north of Prague, to prevent chemicals from spilling into the river.