Police are seeking the public's help into a fatal boating accident off Bunbury.
Four people were onboard a vessel off The Cut when it was struck by a wave, causing it to flip upside down around 1pm on October 3.
"A coordinated rescue involving Water Police, local volunteer Marine Rescue crews, and the RAC Rescue Helicopter commenced," a WA Police spokesperson said.
A male teenager suffered critical injuries and was taken to Bunbury Regional Hospital where he later died.
Three adults, one man and two women, were located safe and uninjured.
Anyone with CCTV, dash-camera or mobile phone vision, which may assist investigators can upload it via this link: https://wapf.au.evidence.com/.../comm.../public/marinerescue
Bunbury Police will prepare a report for the Coroner.

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