David Haw: Missing man fell from boat after it hit buoy in Poole Harbour
The boat a missing man fell overboard from had crashed into a buoy, the Marine Accident Investigation Branch (MAIB) has said.
David Haw, 24, from Sussex, fell from a rigid inflatable boat (RIB) in Poole Harbour in the early hours of Monday.
MAIB said the RIB had "collided with a navigation buoy".
A 19-year-old man from the Southampton area arrested on suspicion of manslaughter has been released under investigation.
Dorset Police said three people were reported to have been onboard the RIB.
A MAIB spokesperson said: "We were notified of a tragic accident that occurred in the early hours of Monday morning when a rigid inflatable boat (RIB) collided with a navigation buoy in Poole harbour.
"Inspectors have attended the accident site, inquiries are being made and a preliminary assessment of evidence is being undertaken.
"A decision on whether an investigation will be launched will be taken in the coming days."
Police divers, the RNLI, coastguard and volunteer teams have been searching the area for Mr Haw since his disappearance.
Supt Gemma Morris, of Dorset Police, said: "But very sadly we have so far been unable to find David.
"While both the wide and targeted searches are now complete, we will continue in our efforts and inquiries to find David and will respond to any information that becomes available to us."
Mr Haw is described as white, 5ft 10in tall, of slim build, with short mousey brown hair. He also has a short beard and bushy eyebrows.
Yacht racing at the Poole Regatta, which had been taking place over the bank holiday weekend, was abandoned.
In a statement, organisers said: "The regatta committee and all of the yacht clubs of Poole are assisting the emergency services with the use of their facilities, staff and boats.
"Our thoughts remain with David's family and friends for a positive outcome."
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