A woman and a firefighter have drowned and hundreds of people in the Balkans have been evacuated from their homes as rain-swollen rivers flooded roads, bridges and railways, closed schools and cut off power and phone service.
In Serbia, nationwide emergency measures were declared and landslides were reported in many areas. Dozens of buses and cars were stranded on blocked roads and two main north-south railway lines were impassable, officials said.
"What we are facing is the biggest water catastrophe in Serbia's history," Prime Minister Aleksandar Vucic said.
In neighbouring Bosnia, meteorologists said the rainfall was the biggest since measuring started 120 years ago. River levels rose all over the country, including the capital of Sarajevo.
Maglaj, 100 kms (60miles) north of the Bosnian capital, was cut off by water surging streets. Some residents sat on house roofs waiting for help.
"The situation is alarming," said Mehmed Mustabasic, the mayor of Maglaj. "We have no electricity, the phones are not working. We are cut off from the rest of the world."
Bosnian military helicopters were employed to evacuate hundreds of people.
In Serbia, emergency officials said that more than 500 people have been evacuated. In some areas, special police and army troops stepped in, while thousands of people have been left without electricity and phone service.
"We have engaged all our manpower," said Predrag Maric, a Serbian emergency official. "Waters are rising everywhere."
Belgrade city authorities closed schools for Thursday and Friday. They say the average rainfall from a two-month period fell on the city in just 40 hours.
Firefighters say a woman in a suburban area of Belgrade drowned after she refused to be evacuated from her home, while the firefighter died during a rescue operation in central Serbia.
The rain is expected to persist until the weekend.