The day after a bus crashed near Venice, killing 20 tourists from countries including Ukraine and Germany as well as its Italian driver, the authorities identified eight victims and said they were working to find the cause.
The death toll remained at 21, but 15 people were injured and nine of them were hospitalized in intensive care, officials said.
Survivors included travelers from Austria, Croatia, France, Germany, Spain and Ukraine, and at least three of them were minors, said Michele di Bari, the prefect of Venice. At least two of the dead were minors, too, but their identities had not yet been verified, he added.
“Identifying people is very delicate,” Mr. di Bari said in a phone interview. “We have a responsibility not to rush any information.”
The president of the Veneto Region, Luca Zaia, visited wounded tourists at a hospital in Mestre on Wednesday. He said one, a 3-year-old girl, had major burns on her body, and that the authorities were “seriously concerned” about her condition. He added that two Austrian siblings, ages 3 and 13, had lost their mother and her partner in the crash.
The electric bus was transporting 35 tourists back from Venice’s city center to a camping site near Marghera, a town on the mainland near Venice.
The authorities said the bus had deviated from its route on an overpass outside of Venice and broken through the metal guardrail on the roadside, plunging more than 10 meters down to an empty road below. The cause of the crash is not known.
CCTV footage showed the bus driving slowly on the overpass and passing another larger bus just before hitting the guardrail.
Bruno Cherchi, the chief prosecutor of Venice, said that his office was investigating the crash, and noted that there were no signs of braking on the overpass. He said the bus, which did not strike any other vehicles, first made contact with the guardrail about 50 meters before it broke through the barrier.
La Linea, the transport company that operates the bus service, said that the bus was equipped with cameras and a black box. Investigators are reviewing the equipment to determine what happened on board.
Massimo Fiorese, the chief executive officer of La Linea, told the Italian news agency ANSA that the overpass guardrail was very thin and resembled more of a “balustrade.” But, he added, it was hard to blame the guardrail, because “it was not the guardrail that went crashing against the bus.”
Venice city officials said that the 70-year-old overpass was undergoing renovations costing 7 million euros, or $7.3 million.
“With such an enormous weight, like a truck or a bus that weighs several tons, no guardrail can hold,” Renato Boraso, a Venice councilman, said in televised remarks. “Even if there was a triple guardrail, it would have been smashed.”
But Felice Giuliani, a professor of road infrastructure at the University of Parma, said that road barriers are designed to contain such impacts, and that the guardrail in Mestre was “inadequate.”
“The problem is that in Italy, the laws and the general attention is very focused on new projects, and much less on the existing infrastructure,” Mr. Giuliani said in a phone interview. “A guardrail like the one in Mestre could never be built on an overpass or a ramp today.”
Footage from the site of the crash, which took place just before 8 p.m. on Tuesday, showed a thick plume of smoke pouring out of the bus, which was upside-down beneath the overpass. Tourists who had managed to emerge from the wreck were on their feet, screaming.
Firefighters said that the bus was on fire when they arrived on the scene, and they had to extinguish the flames and cut through the wreckage before they could extract passengers.
“The impact was tremendous,” Mauro Luongo, the commander of the local firefighters, said, adding that seeing so many people in a single crash was difficult. “It’s a disaster, a tragedy.”