Comic-Zeichnung: Ein Tanker rammt in New Orleans ein am Kai liegendes Flusskreuzfahrtschiff

The passengers of the American Heritage had spent eight days drifting down the Mississippi and were in the middle of disembarking when the river turned on them. Shortly after midday on Friday, a much larger tanker ploughed into the side of the docked paddle-wheeler in New Orleans, and within minutes the cruise boat had rolled over beside the quay.

The ship that hit it was the Atlantic Asphalt, a 160-metre asphalt and bitumen carrier flagged in the Marshall Islands, heading upriver a short distance downstream of the Crescent City Connection. Footage from the waterfront shows its bow crunching into the 81-metre riverboat at about 12:30 local time. According to the Coast Guard, the tanker appears to have suffered some kind of steering loss, while stressing that the cause has not been established.

The riverboat went over while the evacuation was still under way, so many people ended up in the water. Tug crews, dock workers, police and firefighters hauled them out, most of them wearing life jackets. Port figures put the number of guests at about 129, plus the crew. By evening Mayor Helena Moreno could report that nobody was unaccounted for, describing it as a “miracle on the Mississippi”. Hospitals treated 32 people, among them two officers, and none was in a critical condition.

American Cruise Lines moved everyone into hotels, and Governor Jeff Landry credited first responders with saving countless lives. The Coast Guard shut a three-mile stretch of one of America’s busiest commercial waterways while crews worked at the scene.

Federal accident investigators from the NTSB were due in the city on Saturday. Their central question will be how an ocean-going ship came to strike a moored passenger vessel on a crowded bend where tankers, tugs, barges and cruise boats routinely pass within metres of each other. Ship-tracking data show the Atlantic Asphalt had reached New Orleans from New Jersey only two days earlier.