Emergency services were called after a person went into the river.
It happened at Naburn near York, shortly after 2.30pm yesterday (Sunday). North Yorkshire Fire and Rescue said they had been called out to reports that someone had jumped into the marina to rescue their dog.
Police responded to the emergency too and also called out York Rescue Boat, who headed to the scene.
But they were stood down en route as a local boat owner had rescued the person. They were placed into the care of the Yorkshire Ambulance Service.