A state of emergency has been declared in the Macedonian capital Skopje and neighbouring districts, a day after at least 21 people died in flash floods caused by a storm.
Torrential rain flooded homes, swept away a section of the ring road around Skopje and destroyed cars late on Saturday night.
A police spokeswoman confirmed children were among the dead and said the search will continue for six people reported missing.
Macedonia, a small former Yugoslav republic of about two million people, has declared that Monday will be a day of national mourning, after announcing a state of emergency on Sunday.
"This is a catastrophe of unprecedented magnitude," Deputy Prime Minister Nikola Todorov said.
Special police forces and trucks loaded with drinking water have been sent to the worst affected areas, where there also have been some electricity outages and where scattered debris from homes can been seen on the streets, a Reuters reporter said.
By Sunday night the rain had stopped and water levels were receding.
Further north in the Balkans, in Croatia, heavy winds caused disruptions on some roads, including the closure of the highway linking the capital Zagreb to southern coast for trucks and buses, according to local media.
