At least 21 people have died after a coach fell 30 metres from an overpass and caught fire near Venice in northern Italy.
Another 18 people were injured in the crash on Tuesday evening, with Italian police confirming there were tourists of "various nationalities" on board.
There were at least two children among the passengers.
"Several of the victims were foreigners, we found Ukrainian passports," said Venice Mayor Luigi Brugnaro.
Mr Brugnaro described the incident as a "terrible tragedy", adding: "I immediately ordered the city to go into mourning, in memory of the many victims who were in the crashed bus.
"An apocalyptic scene, there are no words."
❌ #Marghera (VE), bus precipitato da cavalcavia: 15 persone soccorse dai 60 #vigilidelfuoco al lavoro, conclusa l’ispezione all’interno del mezzo. Verifica in corso per escludere presenza di persone sotto il pullman [#3ottobre 22:00] pic.twitter.com/LyCjmScE5j
— Vigili del Fuoco (@vigilidelfuoco) October 3, 2023
The coach fell close to railway lines after veering off a road in the district of Mestre, which is connected to Venice by a bridge.
Police said the bus was rented for guests by a campsite in Marghera.
According to Sky Italia, 18 bodies have so far been recovered from the wreckage.
The coach fell on to electricity lines and caught fire. The cause of the accident was still unclear.
Sunday Independent columnist in Italy, Paddy Agnew, told Newstalk Breakfast all the passengers on the bus were tourists.
"The people who died were Ukrainians, Germans, French and Croats - they were all tourists," he said.
"There was only one Italian who died in this, and that was the driver, a 40-year-old man.
"A lot of speculation concerns him because looking at the dynamics of the crash, it seems fairly obvious that he must have had some physical problem.
"Nothing else can explain the dynamics of the crash."
Mr Agnew said camera footage shows what happened.
"This was a shuttle bus that was going between a campsite just outside Venice and Venice," he said.
"At about 7.40 last night [the bus driver] was driving his busload of tourists back to their campsite.
"He gets on to the huge spaghetti junction system... the camera footage on the motorway proves this," he said.
"When he should have been turning left and going down a slip road to get on to his own road, he simply fails to make the left turn and he goes straight off over the side of the flyover," he added.
Italy's Prime Minister Giorgia Meloni said: "I express my deepest condolences, my personal and that of the entire government, for the serious accident that occurred in Mestre.
"My thoughts are with the victims and their families and friends.
"I am in close contact with the Mayor Luigi Brugnaro and with the Minister (of the Interior) Matteo Piantedosi to follow the news on this tragedy."