Television pictures showed mountain rescue squads heading from Civita, the nearest town, to reach the gorge. The most seriously injured were taken by helicopter to hospital in Cosenza.
About 11 people were killed in southern Italy when they were washed away over rocks by a raging white-water creek in a deep mountain gorge that swelled suddenly after heavy rain.
The civil protection department said 23 people were rescued and about a dozen others were hospitalised after surviving the flash flood in the narrow gorge in the Calabria region. The 11th victim died in hospital.
It was unclear how many people were missing but there were at least 36 hikers in two organised groups inside the seven and a half mile long gorge, a popular aquatic trekking spot. TV images show rescuers scaling down the side of a steep rock face to bring hikers to safety.
Guides are not required, making it impossible to know how many people were on their own inside the canyon.
The nationalities of the dead and injured were not immediately known, but most tourists and trekkers who visit the country’s deep south are Italian.
“This gorge filled up with water in a really short space of time and these people were catapulted out like bullets. They ended up some three kilometres (two miles) down the valley,” said Carlo Tansi, head of the civil protection department in Calabria.
“It is really difficult terrain, filled with obstacles because of the (geological) formation of the area,” said Eugenio Facciolla, the chief prosecutor of the provincial capital, Cosenza.
He said rescuers working under spotlights were trying to locate areas where some people may have survived by ending up on small patches of shore or tiny islands in the creek.
Helmeted mountain rescue squads rushed from the nearest town of Civita to reach the gorge, a popular tourist attraction in summer.
“The problem is we don’t know how many people were knocked over by this flood,” Carlo Tansi, the head of civil protection in Calabria, told Sky TG24. “This is a split in the terrain that is very tight and high.”
Luca Franzese, of the alpine rescue squad in Calabria, said the height of the flood waters was some eight feet deep.
“The wave of flooding of the Raganello stream happens often in the winter, but it has never happened in the summer, when the stream is very popular among tourists,” Franzese told the news agency ANSA.
The gorge on the eastern side of the Pollino National Park boasts aquatic trekking along the stream that cuts through the massive rock, where hikers pass by water falls, water tubs and natural slipways, according to a website.
The gorge is broken down into three sections, the upper, mid and lower canyons, with hikes averaging between 2 and a half and 3 and a half hours and varying in difficult.