The ferry, called the Eagle Express, rammed into the dock in the North Frisian island of Amrum while trying to dock at 11am. The ship's steering system appeared to fail and didn't respond to the captain's commands.
It hit the dock on the North Sea island at a speed of eight knots (15 km/h) with 233 passengers on board, including several school classes and elderly people.
Seven rescue helicopters, a rescue boat and paramedics were called and all those who were seriously injured were taken to hospital on the mainland.
The boat, which is almost 42 metres long, can travel at a speed of 24 knots and was launched in 1993.
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