A bus carrying more than 30 passengers careened off a central Spanish highway and ploughed into a metal safety barrier, killing nine people in an impact that blew out windows and tore away one side of the vehicle.
Another 22 people were injured, five seriously, when the bus came off the road as it travelled downhill on a winding road near Avila northwest of Madrid, trapping several passengers in the wreckage, emergency services said.
The blue single-decker bus, which carried the markings of a private bus company, Cevesa, ended up nearly on one side, a buckled safety barrier preventing it from sliding further down a roadside slope.
Windows on the entire right-hand side of the bus were torn away and the buckled frames left exposed after the bus apparently scraped along a rocky wall before striking the metal barrier.
The bus's broken windscreen hung open like a curtain.
"Nine people have died and 22 have been injured," said a statement by the emergency services for the region of Castile and Leon.
It was Spain's deadliest bus crash in five years.
A dozen ambulances, two medical helicopters and teams of firefighters converged on the scene.
Six bodies lay on the N-403 road, covered in white sheets or shiny gold and silver foil.
Emergency services workers in black helmets and tunics carried one person away on a stretcher. Shocked passengers sat on the kerb nearby, some being comforted by first aid personnel.
A female rescuer in white shirt and bright-orange vest could be seen placing a neck brace on a man lying on a yellow stretcher on the roadside, images relayed on Spanish media showed.
The bus had been heading to the provincial capital Avila from the province's southern town of Serranillos and was less than 10 kilometres (six miles) from its destination when disaster struck at about 8:45 am (6.45pm NZT).
"It came off the road for unknown reasons," said the central government representative for Avila, Ramiro Ruiz Medrano.
"They are investigating the possible causes at the moment," Medrano told Spanish public radio.
"There are some with very serious injuries, others are in shock," he said.
The driver was uninjured, Medrano said, though Spanish media said he was in shock.
The vehicle's insurance papers and road worthiness certificates were in order, he added.
The injured were taken to hospitals in Avila for treatment or medical examination, emergency services said.
A six-year-old girl was flown about 100 kilometres by helicopter to a major hospital in Salamanca.
"She is stable but they have to examine her for trauma to the brain," the mother, who was not named, told Spanish public radio.
A 17-year-old girl and a 91-year-old were later taken to the same Salamanca hospital.
At the Sonsoles Hospital in Avila, 63-year-old Lucia Herranz told AFP her granddaughter Lucia Garcia, 16, was in the bus with two girlfriends for a day out shopping in Avila.
"She has some broke bones in her wrist," Herranz said. "When she arrived she was in shock. It was very intense. She was trembling and crying because she had two friends in the bus."
One of her girlfriends was the 17-year-old patient rushed to the Salamanca hospital with a serious head injury. The other girl, 16, required a few stitches in her leg but suffered no broken bones, according to her family.
A team of psychologists was comforting the victims' families, who were taken to the Avila sports stadium.
It was the deadliest bus accident in Spain since April 2008 when nine Finnish tourists were killed in a crash in southern Spain's Andalusia region.
That accident was blamed on a drunken, speeding driver of a four-wheel-drive car who tried to overtake but hit the safety barrier and then collided with the bus.