Contestants are being pulled out of the water at the 12km mark where a 3-4 metre shark has been seen and a boat has sunk during the Rottnest Channel Swim, but organisers say the event is not being cancelled.
A support boat has started sinking around 8 kilometres into the Channel Swim.
Fremantle Sea Rescue have attended a 9 metre boat and rescued all five crew members.
PIC: Supplied by Fremantle Sea Rescue
PIC: Supplied by Fremantle Sea Rescue
Meanwhile, swimmers are being pulled from the water at the 12 kilometre mark due to a shark sighting.
The shark is believed to be between three and four metres long, but organisers say the swim has not been called off.
Solomon Wright was the first man to complete the swim solo, finishing in 3 hours, 59 minutes and 28 seconds, and Heidi Gan was the first woman across the line completing the swim in four hours and 21 minutes, coming in overall fifth.
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