An elderly woman has been found dead after being thrown overboard in a boating accident.
Emergency services were called to a stretch of water known as the Marion Narrows at Marion Bay in Tasmania's southeast on Wednesday morning following reports of a boating incident.
Three of four passengers in a 4.5 metre fibreglass runabout were thrown into the water after it likely became caught in the chop of a passing vessel.
Onlookers on a nearby vessel rushed to their aid but were only able to locate and retrieve two men.
A woman, believed to be in her 70s, was not found until her body was located a short time later.
Initial reports suggested the boat had capsized, but police now believe it simply veered to its side in the wake of a passing vessel.
"We think they've either hit a wave or some chop from another boat and that has potentially caused their boat to veer to one side, which has then caused the three people to be thrown into the water," southern district commander Jason Elmer said.
"This appears to have been a freak accident."
All three passengers were believed to have been wearing personal flotation devices.
