A towering cruise ship has crashed into a dock and a tourist river boat on one of Venice’s busiest canals.

Four people were injured in the smash, Venice port authorities reported.

It happened on the Giudecca Canal – a major thoroughfare that leads to Saint Mark’s Square – on Sunday morning at 8.30am.

Video of the crash shows the 80-metre cruise ship apparently unable to halt its momentum, blaring its horn as it ploughs into the much smaller river boat and the dock as dozens of people run away in panic.

“Some scared passengers dived into the water, while others fled the boat,” Venice resident Ida Ossi told local media.

Venice cruise ship crash – in photos Show all 15 1 /15 Venice cruise ship crash – in photos Venice cruise ship crash – in photos The damaged River Countess tourist boat is pictured after it was hit by the MSC Opera cruise ship that lost control as it was coming in to dock in Venice, Italy AFP/Getty Venice cruise ship crash – in photos MSC cruise ship losing control Reuters Venice cruise ship crash – in photos Tourists on land could be seen running away as the MSC Opera scraped along the dockside, its engine blaring, before knocking into the River Countess tourist boat Reuters Venice cruise ship crash – in photos MSC Opera before crashing Robert Lauretti via Reuters Venice cruise ship crash – in photos Italian Coast Guard officers inspect the tourist boat that was struck AP Venice cruise ship crash – in photos Italian media reported that at least five people have been injured in the crash AP Venice cruise ship crash – in photos The MSC cruise ship Opera is seen after the collision with a tourist boat, in Venice, Italy, Sunday, June 2, 2019. The towering, out-of-control cruise ship rammed into a dock and a tourist river boat on a busy Venice canal on Sunday morning. Italian media reported that at least five people were injured in the crash. The collision happened about 8:30 a.m. on the Giudecca Canal, a major thoroughfare that leads to Saint Mark's Square in the northeastern Italian city. (Andrea Merola/ANSA via AP) Andrea Merola ANSA via AP Venice cruise ship crash – in photos Members of Venice's "No Big Ships" Committee (No Grandi Navi) gathered to stage a protest after the crash AFP/Getty Venice cruise ship crash – in photos The tourist river boat that was struck by a towering cruise liner, foreground bottom, is dwarfed by the MSC Magnifica cruise liner passing by, in Venice, Italy, Sunday, June 2, 2019. The MSC Opera cruise ship has struck a dock and a tourist river boat on a busy canal in Venice. Italian media report that at least five people have been injured in the crash. (AP Photo/Luca Bruno) Luca Bruno AP Venice cruise ship crash – in photos A partial view of the tourist boat that was struck by a cruise line ship in Venice, Italy, Sunday, June 2, 2019. A towering, out-of-control cruise ship rammed into a dock and a tourist river boat on a busy Venice canal. Italian media reported that at least five people were injured. (AP Photo/Luca Bruno) Luca Bruno AP Venice cruise ship crash – in photos MSC cruise ship loses control and crashes against a smaller tourist boat at the San Basilio dock in Venice, Italy June 2, 2019. REUTERS/Manuel Silvestri MANUEL SILVESTRI Reuters Venice cruise ship crash – in photos The tourist river boat that was struck by a towering cruise liner, left, is dwarfed by the MSC Magnifica cruise liner passing by, in Venice, Italy, Sunday, June 2, 2019. The MSC Opera cruise ship has struck a dock and a tourist river boat on a busy canal in Venice. Italian media report that at least five people have been injured in the crash. (AP Photo/Luca Bruno) Luca Bruno AP Venice cruise ship crash – in photos A boat is seen after a crash with MSC Opera, at San Basilio dock in Venice, Italu June 2, 2019. REUTERS/Manuel Silvestri MANUEL SILVESTRI Reuters Venice cruise ship crash – in photos MSC cruise ship loses control and crashes against a smaller tourist boat at the San Basilio dock in Venice, Italy June 2, 2019. REUTERS/Manuel Silvestri MANUEL SILVESTRI Reuters Venice cruise ship crash – in photos A boat is seen after a crash with MSC Opera, at San Basilio dock in Venice, Italu June 2, 2019. REUTERS/Manuel Silvestri MANUEL SILVESTRI Reuters

Previous reports suggested that five people had been injured, but Venice port authorities later confirmed only four had been. They were taken to the hospital, but none of them sustained serious injuries. Their nationality is not known yet.

Davide Calderan, the president of the company that owned the two towboats steering the cruise ship before the accident, told Italian news agency ANSA that the cruise ship’s engine had a mechanical problem and was locked when the captain called for help.

Aftermath of collision between Venice cruise ship and tourist boat

“The two towboats were trying to stop the giant until one of the tow cables broke, cut in the collision with the river boat,” he said.

Local activists have campaigned for Venice to ban large cruise ships from entering the lagoon for years to protect its ecosystem and the incident has revived calls for the ban.

Activists were seen protesting on the scene of the accident.

“Today’s accident in Venice’s port demonstrates that large ships can no longer sail on the Giudecca canal,” Italy’s infrastructure minister Danilo Toninelli tweeted.

“After years of inactivity, we are finally close to a definitive solution to protect both lagoon and tourism.”

Venice mayor Luigi Brugnaro demanded the opening of alternative routes for cruise ships to reach the city in a Facebook post. “It’s no longer thinkable that large ships sail on the Giudecca Canal,” he wrote.

Venice attracts some 28 million visitors each year, or 76,000 per day.