An off-duty doctor went to the aid of a man who was in need of medical help after being in the Leeds and Liverpool Canal at Brierfield on Friday night.
The man (51) had managed to pull himself from the canal when he was found, but then tried to get back into the water despite needing urgent medical attention.
Police were called to the incident near the bridge at Clitheroe Road at 7-25pm.
Insp. Andy Carter of Burnley Police said that the man was sectioned under the Mental Health Act for his own safety.