Two people were killed late Tuesday when a mudslide swept into a house in the Celje region, some 80 kilometres (50 miles) north of Ljubljana, and two more died earlier in the day in the Cerklje region, some 60 kilometres (35 miles) northwest of the capital, the station said.

Another four peeople, including a mother and her nine-year-old child, are still missing, the radio quoted local authorities in the region as saying.

The rains, which dumped up to 300 litres of water per square metre in only a few hours in some places, were the heaviest registered in the last three decades, the Slovenian Defense and Rescue agency said.

The agency said that more than 350 houses had been flooded or damaged in the Gorenjska region and especially in the town of Zelezniki, some 60 kilometres northwest of Ljubljana, where the Sora river inundated the centre, carrying away more than 150 cars.

The Slovenian government promised urgent measures to help local people.

Traffic on many roads in the Gorensjka region was still disrupted Wednesday while many villages were without electricity or drinking water, or were cut off because of damaged roads.

The Sora river also swept away 11 out of 13 wooden buildings that were part of the Franja Hospital museum, built by anti-Nazi fighters during World War II in a nearby mountaneous region.

Slovenia wants the museum to be included in UNESCO's world heritage list.