A bus went off a winding road and plunged into a ravine in central Bolivia early on Monday, killing at least 13 people and injuring 37 others, police said.
Survivors said the driver was speeding as the bus neared the city of Cochabama, 400 kilometres east of La Paz, before dawn.
"We were sleeping and I woke when passengers began screaming at the driver to stop," said Leticia Costa, who was among the injured taken to local hospitals.
"He accelerated even more and in one of the turns we went off the side of the road and bus hurled over the side," she said.
Cristina Cerruto, commandant of the Highway Police of Cochabamba, told the Erbol radiostation that the preliminary toll stood at 13 dead and 37 injured.
"The ravine was approximately 40 metres deep,"