Heavy snowfall across eastern Europe cut off hundreds of villages on Tuesday and rescue teams struggled to evacuate people in southern Bulgaria where rain and melting snow had caused a dam wall to break, flooding an entire village.
A river dike also broke under intense water pressure near Kapitan Andreevo at the border with Turkey, officials said.
The cold snap has killed hundreds of people across Europe and temperatures in some countries plummeted to nearly minus 40C (minus 40F). Officials on Tuesday warned of flooding when temperatures rise and snow melts.
Around 146 towns and villages in Romania were isolated with no road or train connections because of blizzards. Up to 174 villages had no electricity, said Alin Maghiar, spokeman for Romania's emergency department.
Electricity was also cut off to 300 towns and villages in Bulgaria, roads were closed and several border checkpoints with Romania and Turkey were shut, the Interior Ministry said.
The ministry said more heavy snowfall was expected.
Melting snow had caused a dam wall to break and flood an entire village in southern Bulgaria on Monday. Four people drowned and more than 50 were evacuated. Four more people died when their cars were swept away by high waters.
It was terrifying, Iliyan Todorov from the village of Biser told Trud daily. We were warned that the tsunami was coming only five minutes before the wave came...We survived by a miracle.
European Commissioner for Crisis Response Kristalina Georgieva said the worst is yet to come after visiting Biser.
The next two weeks may be really hard. The warmer weather will cause melting of the snow and the situation will most probably worsen, private broadcaster bTV quoted her as saying.
In the worst affected country, Ukraine, 135 people were confirmed dead up to Monday and forecasters said bitter temperatures, as low as minus 30 Celsius (minus 22 Fahrenheit), would continue until at least February 15.
RIVER ICE THREATENS CITY
The Black Sea ports of Varna and Burgas have been closed due to strong winds and Romania's main port of Constanta and other smaller ports were also shut down on Tuesday.
Authorities in Serbia said they were preparing to use explosives to break ice on the rivers Ibar and Danube.
An ice cap half a metre deep has formed on the Ibar near Kraljevo and there is a real danger that it could cause the river to overflow into the city, said Predrag Maric, head of the Interior Ministry's emergencies department.
He said 100 km (62 miles) of the Danube were freezing over and that it would also be mined.
Eleven people have died so far from the cold and snow in Serbia, with the latest victims a 62-year-old man found dead a kilometre from his home near Arilje in western Serbia and a woman killed by falling ice in the capital Belgrade.
Serbian power provider TENT, which provides more than 60 percent of the country's electricity, said it was managing to maintain supplies but was working at full capacity in extreme conditions.
To the south in Albania, the Kukes lake on the border with Kosovo - supplying a hydropower plant at Fierze - was frozen over for the first time in more than a decade, putting more pressure on already strained power supplies.
The cold weather has increased demand for gas in many European countries.
Italy took emergency measures on Monday to deal with what it called critical shortages of Russian gas. Supplies to other members of the European Union mostly improved at the weekend but remained below normal.
Russia, which supplies about a quarter of Europe's natural gas, reduced westward flows through pipelines across Ukraine last week citing greater domestic demand because of the extreme weather.
(Reporting by European Bureaux; Writing by Diana Abdallah; Editing by Ben Harding)