(QHA) -

At least 33 people have died and tens of thousands have been evacuated in Serbia and Bosnia during three days of torrential rains that fed the most intense flooding the region has seen since records began to be kept more than a century ago.

The authorities have called for international help to rescue people from inundated areas after the worst flooding since modern records began.

A large international aid operation is underway, with rescue helicopters from the European Union, US and Russia evacuating people from affected areas.

Waters are now beginning to recede, but officials say dangers remain.

They say that the threat of landslides is an ever-present problem as are the difficulties caused by unexploded landmines in Bosnia and river surges.

Serbia's main power plant is still at risk of flooding.