In a potentially deadly side-effect to the record-breaking floods that have engulfed Bosnia, officials warned on Monday that unexploded mines left over the 1990s conflict could be dislodged and moved.

"Water and landslides have possibly moved some mines and taken away mine warning signs," said Sasa Obradovic, an official of Bosnia's Mine Action Center.

Thousands of people crammed into boats and army trucks fled their homes in Serbia and Bosnia Sunday after record rainfall turned the Sava river into a deadly torrent and caused the worst floods in more than a century.

According to officials in both countries, the disaster has killed at least 44 people. Some towns have been completely cut off and rescue teams feared the worst as improving weather allowed them to move in.

At least 30 people have died in last three days in the worst floods to hit Bosnia and Serbia in a century, officials said Saturday.

"More than 20 corpses have so far been brought to the city's morgue," the mayor of northern Bosnian town Doboj Obren Petrovic told Bosnia's FTV public broadcaster.

The heaviest rains in more than a century have sparked floods across Bosnia and Serbia, claiming at least 16 lives and leading to the evacuation of some 15,000, officials said Saturday.

"Six bodies were found in the northern Bosnian town of Doboj after floods started to withdraw from the streets. Unfortunately, this is probably not the final toll," Milorad Dodik, president of Serb-run entity in Bosnia, told reporters.

Three people have drowned in Serbia and hundreds have been evacuated following flooding caused by torrential rain that prompted authorities to declare a state of emergency, officials said on Thursday.

"A man who refused to leave his home as suggested by rescuers drowned overnight in Umcari," a southwestern suburb of the Serbian capital Belgrade,  mayor Sinisa Mali said, quoted by the state-run RTS television.

Severe flooding in Serbia and Bosnia has forced schools to close and hundreds of people to evacuate their homes and left thousands more without power.

In Serbia one person has drowned and a state of emergency has been declared in the worst-hit areas after two days of torrential rain.

The new prime minister of Serbia traveled to Bosnia on Tuesday, pledging to respect borders and rebuild ties that remain tense nearly two decades after the devastating conflict that tore the region apart.

"I arrived for a visit to Sarajevo and Bosnia-Hercegovina as a friend, as someone who represents a country that respects the territorial integrity of Bosnia," Serbian Prime Minister Aleksandar Vucic told reporters after meeting his Bosnian counterpart Vjekoslav Bevanda.

Serbia should focus on economic reforms, the implementation of rule of law and further negotiations with breakaway Kosovo as it works toward becoming a member of the European Union, an EU official said Monday.

"We are fully committed to help Serbia with the necessary reforms," EU Enlargement Commissioner Stefan Fuele told reporters in Belgrade after meeting Serbian President Tomislav Nikolic.

The European Union will help Serbia's new EU-hopeful government implement ambitious economic reforms, the bloc's foreign affairs chief Catherine Ashton said Monday.

"The EU is determined to help and support Serbia in its efforts to ensure a strong economic path for its people," Ashton told reporters after meeting new Prime Minister Aleksandar Vucic, who was sworn in Sunday at the head of a center-right government after a snap election on March 16.

Kosovo's parliament approved on Wednesday the establishment of an international court to deal with alleged crimes committed by ethnic Albanian guerrillas during the 1998-1999 war with Serbia.

The vote came amid a mounting pressure on Pristina to back an EU call to create a special court to address the allegations detailed in a 2011 Council of Europe report on crimes committed by pro-independence ethnic Albanian Kosovo Liberation Army (KLA).