A 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, The Guardian reported.

The collision happened at about 8:30am on Sunday on the Giudecca Canal, a major thoroughfare that leads to St. Mark’s Square.

The cruise ship, apparently unable to stop, plowed into the much smaller river boat and the dock.

“The MSC ship had an engine failure, which was immediately reported by the captain,” Davide Calderan, the 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.”

The two tugboats that had been guiding the ship into the Giudecca tried to slow it, but one of the chains linking them to the cruise ship snapped under the pressure, he added.

Venice’s port authority said it was working to resolve the accident and free up the blocked canal.

As a result of the collision, four people in the small vessel suffered injuries and one person—aboard the cruise ship, and some passengers fell in the water.

The Venice port authority is evacuating the passengers of the ship.

Police, rescuers, and firefighters are at the scene.