A colossal cruise ship crashed into a smaller tourist boat and a dock in Venice on Sunday, injuring at least four tourists.
Footage of the collision shows an approximately 900-foot-long MSC Opera blaring its horns and failing to slow down as it approached the San Basilio Terminal on the Giudecca Canal. A much smaller tourist boat, the River Countess, was docked and couldn’t move away from the terminal in time.
Four female tourists, including one American, were injured while falling or trying to run away, according to the Associated Press.
The incident incited renewed calls to block off the cramped Giudecca canal from large vessels that drop off up to tens of thousands of visitors in the Italian city each day.
The cruise ship’s operator, MSC, attributed the collision to a “technical problem” in a statement.
MSC said it was performing an investigation to “understand the exact dynamic of the facts,” the operator said, according to the New York Times.
Italy’s Minister of the Environment, Sergio Costa, said the crash proved what experts have long been warning.
“What happened in the port of Venice is the confirmation of what we have been saying for a long time: big ships must not pass by Giudecca,” he tweeted in Italian.
The Northeastern Italian city passed an ordinance in 2013 that sought to ban ships over 96,000 tons from entering the port, and reduce by 20% the number of ships over 40,000 tons, but the ban was suspended only months later after a regional court argued that alternative routes were not yet in place, and that the risks the large ships posed were not yet proven.
In 2017, Italy banned the largest cruise ships from Venice’s Grand Canal, but also estimated it would take four years before the new port in a nearby town was complete, according to the BBC.
Venice Mayor Luigi Brugnaro urged immediate action to open an alternative route, according to Italian news agency, ANSA.
“It’s no longer thinkable that big ships can pass through the Giudecca Canal,” Brugnaro said. “Now we must urgently make sure that ships no longer pass in front of St. Mark’s.”
According to the cruise line, the MSC Opera is 65,591 tons, has 1,071 staterooms and fits 2,150 passengers and 728 crew members.
More Must-Reads from TIME
- Introducing the 2024 TIME100 Next
- Sabrina Carpenter Has Waited Her Whole Life for This
- What Lies Ahead for the Middle East
- Why It's So Hard to Quit Vaping
- Jeremy Strong on Taking a Risk With a New Film About Trump
- Our Guide to Voting in the 2024 Election
- The 10 Races That Will Determine Control of the Senate
- Column: How My Shame Became My Strength
Write to Abby Vesoulis at abby.vesoulis@time.com