Large ships are playing “Russian roulette” with Venice, it was claimed as thousands of people took part in two days of anti-cruise protests in the Italian city.

Small boats rallied for a protest regatta yesterday after about 6,000 demonstrators marched to St Mark’s Square on Saturday behind a banner reading: “Ships out of the lagoon.”

The campaigners spoke out a week after MSC Opera crashed into a wharf due to engine trouble and hit a Uniworld riverboat, injuring five people.

Dramatic video footage – widely viewed online – showed people on the dock scrambling for cover as 2,150-berth MSC Opera hit the quay and Uniworld’s River Countess after losing control due to a mechanical fault.

A demonstration organiser, Tommaso Cacciari, was reported by The Times as saying: “What happened shows they’re dangerous, they’re out of control in case of failure and they can’t continue to play Russian roulette with our homes, our lives, with our city, just to make these cruise companies rich.”

Protesters said the accident on the Giudecca canal, near St Mark’s, underlined the urgency of routing big ships away from the fragile Unesco world heritage site.

Venice hosts about 25 million visitors a year, with 14 million staying for only one day.

The Italian government banned ships weighing more than 96,000 tonnes from the centre in 2013 but the law was overturned on appeal.

Cruise industry body Clia said cruise lines have been “actively engaged” in discussions for a considerable time about using the Vittoria Emanuele Canal as the preferred alternative solution.

“Clia urges all parties in Venice to reach a conclusion to start the preparation work to prepare the Vittoria Emanuele Canal so we can begin to reroute the larger ships,” the organisation added.

MoreComment: Working together is more important than ever for cruise sector

MSC Cruises collision casts doubt over Venice cruise calls

Cruise lines urge Venice action following MSC ship collision