Poland joins Austria, the Czech Republic and Romania in being hard hit by floods after record rains in the region that started a week ago. Authorities have reported 23 deaths, with seven each in Poland and Romania, five in Austria and four in the Czech Republic.

A massive flood wave moving across Central Europe is threatening new areas and raising concerns among residents and officials.

By Kacper Pempel WROCLAW, Poland (Reuters) -Volunteers and emergency personnel worked through the night to fortify the Polish city of Wroclaw against approaching flood waters, while Hungary opened a dam as the prime minister warned a "crucial period" was approaching.