A 14-year-old girl died after a wave overturned a speedboat she was in causing her life jacket to become trapped, police said.
Emily Gardner was one of four people thrown overboard but the three others escaped with injuries.
Devon and Cornwall Police are continuing to investigate the tragedy but a spokesperson said: "From the enquiries conducted so far, reports suggest that the boat hit a wave before overturning.
"The four people on the boat were then thrown overboard as a result.
"It appears that Emily became trapped due to her buoyancy aid getting caught on part of the boat.
"The other people on the boat and jet ski riders tried to help Emily but could not free her.
"At this stage in the investigation we are satisfied that there are no suspicious circumstances and we believe that this was nothing more than a tragic accident."
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