SOFIA (Reuters) - Three people were killed and one is missing after torrential rains lashed low-laying parts of Black Sea port city of Bourgas and flooded several surrounding villages in southeastern Bulgaria early on Wednesday, local authorities said. The strong rains cut electricity supplies to at least five villages, forced rivers to outburst their banks flooding dozens of homes and blocking roads in Kameno municipality where authorities have declared an emergency situation.        People in the village of Trastikovo, some 390 km (242  miles) east of Sofia, were evacuated after flooding waters broke a dyke. Weather forecasters say strong rains are expected to continue on Wednesday.   