Floods threaten Dresden as Prague river levels fall

Cities in southern and eastern Germany are on high alert as heavy floodwaters swell rivers including the Elbe.

In Halle, an appeal has gone out to residents to help reinforce flood defences while Dresden is preparing for water levels 5m higher than normal.

German Chancellor Angela Merkel has promised 100m euros (£78m; $130m) in emergency aid for flood-hit areas.

Christian Fraser reports from the Czech Republic, where rushing floodwaters are rising at 15cm an hour .