Rescue workers searched Wednesday for six elderly people missing at Kolontar, one of three villages in southwest Hungary that was hit Monday by a wave of toxic red sludge from an alumina plant reservoir that burst.
A unit at a Bulgarian nuclear power station on the Danube River underwent an emergency shutdown Saturday, facility operators said.
Thousands of emergency workers in Romania, Bulgaria and Serbia are trying to bolster dikes along the swollen Danube River, which has surged to its highest level in more than a century.
Helicopters are delivering food and other supplies and lifting hundreds of people to safety in the aftermath of deadly floods in central and southern Europe.