Preston Docks saw two air ambulances land during Tuesday (2 July).
A man was taken ill aboard a boat in the Marina.
Two air ambulances and North West Ambulance Service crews were scrambled to the Docks near the Harbour Lockhouse.
A police spokesman confirmed to Blog Preston a call came in around 1.10pm.
He said: “It looks like a man had been taken ill on Preston Marina.
“He was taken to Royal Preston Hospital for treatment.”
North West Ambulance Service confirmed a man in his 60s had collapsed.
He was in a critical condition when taken to hospital.
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