The passengers sustained their injuries in falls when the boat ran aground at high speed. None were in danger of drowning.
The 50 year-old man who was operating the boat at the time of the accident was badly injured and flown from the scene by helicopter to hospital in Helsinki.
According to the Coast Guard's Maritime Rescue Centre, conditions were not especially windy at the time of the acccident. However, it had been raining and visibility was poor.
Police report that the operator of the boat was tested and found to have an blood alcohol content over the legal limit.
