Agusta Westland helicopter on scene (Image: Tiffany Irvin)
Emergency services have been called to an incident near Largs Yacht Haven.
Ambulance staff were treating a diver showing signs of decompression sickness near The Pencil, according to HM Coastguard.
A coastguard helicopter and two support vehicles were also on the scene, parked near the Championship slipway.
A coastguard spokesperson said: "A diver who was on a recreational dive made a fast assent and showing signs of decompression sickness.
"He has now been flown to Oban for further treatment at a hyperbaric chamber, after being assessed by Scottish Ambulance staff.
An Agusta Westland helicopter took the diver to a hyperbaric chamber in Oban for further treatment earlier this afternoon.
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