A bus careered down a mountainside and plowed through a crowd of pedestrians heading to a religious festival in southeastern Bulgaria on Thursday, killing at least 16 people and injuring at least 20, authorities said.
Police said the driver apparently lost control of the vehicle after its brakes failed. He could not stop as the bus came down a mountain pass, hitting a crowd of people climbing to the peak on their way to attend a traditional Ascension Day feast near the city of Yambol, some 260 kilometers (160 miles) southeast of Sofia.
Yambol Mayor Georgi Slavov said 16 people were killed and at least 20 were being treated in a nearby hospital. Four of the injured were listed in very serious condition.
The government said Friday would be an official national day of mourning for the victims.