Rome: A cruise ship lost control as it was coming in to dock in Venice Sunday, crashing into the wharf and hitting a tourist boat, Italian media reported.
Tourists on land could be seen running away as the MSC Opera scraped along the dockside, its engine blaring, before knocking into the Michelangelo tourist boat, amateur video footage posted on Twitter showed.
Two people were lightly injured in the accident at San Basilio-Zattere in the Venice's Giudecca Canal, according to the media reports.
Another two were taken to hospital for check-ups. Their nationalities were not known, the reports said.
The crash may have happened after a cable used to link cruise ships to the tug boats that pull them into the city's canals broke, the Corriere della Sera daily said.
The Opera was then unable to stop because of the strong currents pulling it towards the dock, it said.
MSC Cruises, founded in Italy in 1960, is a global line registered in Switzerland and based in Geneva. The Opera, built 15 years ago, is registered in Panama and has a capacity for 2,679 passengers.
The Opera, which suffered mechanical trouble before in 2011 during a Baltic cruise, can carry over 2,500 passengers and boasts a theatre, ballroom and waterpark for children.
"The MSC ship had an engine failure, which was immediately reported by the captain," Davide Calderan, head of a tugboat company involved in accompanying the ship into its berth, told Italian media.
"The engine was blocked, but with its thrust on, because the speed was increasing," he said.
The two tug boats that had been guiding the ship into the Giudecca tried to slow it, but one of the chains linking them to the giant snapped under the pressure, he added.
A heated row
The accident reignited a heated row in the Serenissima over the damage caused to the city and its fragile ecosystem by cruise ships that sail exceptionally close to the shore.
While gondoliers in striped T-shirts and woven straw hats row tourists around the narrow canals, the smoking chimneys of mammoth ships loom into sight behind the city's picturesque bell towers and bridges.
Critics say the waves the ships create are eroding the foundations of the lagoon city, which regularly floods, leaving iconic sites such as Saint Mark's Square underwater.
"What happened in the port of Venice is confirmation of what we have been saying for some time," Italy's environment minister Sergio Costa wrote on Twitter.
"Cruise ships must not sail down the Giudecca. We have been working on moving them for months now... and are nearing a solution," he said.
Venice's port authority said it was was working to resolve the accident and free up the blocked canal.
"But from tomorrow we need to move, all together and as quickly as possible, to resolve the cruise ship traffic problem," said Pino Musolino of the North Adriatic Sea Port Authority.
MSC Cruises, founded in Italy in 1960, is a global line registered in Switzerland and based in Geneva.
The Opera, built 15 years ago, suffered a power failure in 2011 in the Baltic, forcing some 2,000 people to be disembarked in Stockholm rather than continuing their Southampton to Saint Petersburg voyage.