The death toll from torrential rain and flooding in central and eastern Europe has risen to at least 16, with several more people missing, as authorities reported deaths in the Czech Republic, Poland and Austria and warned the worst may be to come. The number of victims in Poland rose to five after a surgeon returning from work drowned in the south-western town of Nysa, where the hospital was evacuated and patients rescued by raft. Four more people had died in the southern towns of Bielsko-Biała and Lądek-Zdrój, firefighters said. In Austria, local media reported that two men aged 70 and 80 drowned after being trapped by rising flood water in their homes in the towns of Böheimkirchen and Sierndorf, both in the hard-hit north-eastern state of Lower Austria. The Czech police chief, Martin Vondrášek, told local radio a woman had drowned in a stream that overflowed its banks near Bruntál, a town of about 15,000 people in the north-east of the country, while seven more people were still unaccounted for. Tens of thousands of people were evacuated from their homes across a swathe of Austria, the Czech Republic, Hungary, Romania and Slovakia as Storm Boris unleashed the worst flooding recorded in the region for more than two decades. It was described by one Romanian mayor as a “catastrophe of epic proportions”. The flood water burst dams, inundated streets, knocked out electricity and in some places submerged whole neighbourhoods. “I have lived here for 16 years and I have never seen such flooding,” one Austrian woman, Judith Dickson, told public radio. Seven people died in Romania over the weekend, as well as one in Poland and a firefighter in Austria. The rain was expected to ease in many areas on Monday but, with some rivers unlikely to reach peak water levels for days, several major cities were preparing for potentially disastrous flooding. Extreme rainfall is becoming more common and more intense because of human-caused climate breakdown across most of the world, particularly in Europe, most of Asia, central and eastern North America, and parts of South America, Africa and Australia. Poland’s prime minister, Donald Tusk, declared a state of emergency in the flooded areas and announced an emergency aid fund of 1bn zlotys (£200m), while his counterpart in Hungary, Viktor Orbán, cancelled all his international engagements. Tusk said he was in touch with the leaders of other affected countries and that they would ask the EU for financial help. “From today, anyone affected by the flood – flooding, collapsed buildings, flooded garages, lost cars, losses linked to the flood – will be able to easily [claim funds],” he said. More than 2,600 people were evacuated across Poland in the last 24 hours, according to the defence minister, Władysław Kosiniak-Kamysz. Standing in the town square of Lądek-Zdrój in south-western Poland, Szymon Krzysztan, 16, described the destruction as “unimaginable … It’s a city like in an apocalypse… It’s a ghost town.” Jerzy Adamczyk, 70, said the scene resembled “Armageddon”. He added: “It literally ripped out everything because we don’t have a single bridge. In Ladek, all bridges have disappeared. We are practically cut off from the world.” The German chancellor, Olaf Scholz, described images from the flooded areas in Austria, the Czech Republic, Romania and Poland as “dramatic” and said Germany was “deeply saddened by the news of dead and missing people” and ready to help. Hungary’s capital, Budapest, was bracing for severe flooding as the Danube rose. The interior minister, Sándor Pintér, said efforts were focused on keeping the river and its tributaries within their banks and said up to 12,000 soldiers were on standby. Slovakia’s capital, Bratislava, was also on a high state of alert, while the 600,000 residents of Wrocław in Poland were told water levels might not peak before Wednesday. Austria’s chancellor, Karl Nehammer, said the situation in his country “continues to worsen”, particularly in Lower Austria, which has been declared a disaster area. More than 10,000 relief workers had evacuated 1,100 houses in the state, he said. Lower Austria’s governor, Johanna Mikl-Leitner, said people there were facing “difficult and dramatic hours … probably the most difficult hours of their lives”. The municipality of Lilienfeld, with about 25,000 residents, was completely cut off from the outside world, local media reported. So far 12 dams had broken and thousands of households were without electricity and water, authorities said. “It is not over,” Mikl-Leitner added. “It stays critical. It stays dramatic.” She said there there was a high risk of more dams breaking and it was as yet too early to assess the scale of the damage. The Czech prime minister, Petr Fiala, urged people to “follow the instructions of mayors and firefighters”. As of Sunday evening, he said, emergency services had dealt with 7,884 incidents and 119,000 households were without power. At least 12,000 people had been evacuated from their homes across the country, Fiala said, adding that although the rain had stopped in the most affected areas, the situation would become critical for others as the storm moves westwards and rivers continue to rise. “Very difficult days for many people, unfortunately, continue,” Fiala said on Monday, with 207 areas across the country facing flood conditions. The most critical situation was in southern Bohemia, he said, adding: “Please be careful and responsible.” The rising Morava River put about 70% of the Czech city of Litovel, 140 miles (230km) east of the capital, Prague, underwater overnight, its mayor told local media, shutting down schools and health facilities. In the country’s third biggest city, Ostrava, a power plant supplying heat and hot water was forced to shut down. Thousands were evacuated from their homes in Krnov and Český Těšín. In Opava, up to 10,000 people out of a population of about 56,000 were asked to move to higher ground. “There’s no reason to wait,” the mayor, Tomáš Navrátil, told Czech public radio, saying the situation was worse than during devastating floods in 1997, known as the “flood of the century”. Romania’s prime minister, Marcel Ciolacu, said the country would “clean up and see what can be salvaged”, adding that compared with the worst recent flooding in 2013, “the amount of water was almost three times bigger”. One resident of the Romanian village of Pechea, in the stricken Galati region, told Agence France-Presse: “The water came into the house, it destroyed the walls, everything. It took the chickens, the rabbits, everything. It took the oven, the washing machine, the refrigerator. I have nothing left.” The climate emergency is causing more incidents of extreme rainfall because warmer air can hold more water vapour. Flooding has most likely become more frequent and severe as a result, but other human factors, such as flood defence planning and land use, are also important.