Authorities have not been able to determine if the body of a man discovered in the Susquehanna River Tuesday is that of a York County canoeist who disappeared on Sunday.

Lancaster County Coroner Dr. Stephen Diamantoni said his office is still working to see if it is Robert Brennan, 63, of Wrightsville, who went missing after his canoe capsized just north of Marietta in Conoy Township.

“We are attempting to find dental records to help us make a positive I.D.,” Diamantoni said after an autopsy on Wednesday. “We know he is a middle-aged man and he died from freshwater drowning.”

Brennan’s wife, Catherine, 57, and the couple's dog also were in his canoe. Both made it to shore.

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Crews unsuccessfully searched the river for Mr. Brennan on Sunday and Monday.

On Tuesday, a boater discovered a body in the water near Long Level Marina around 12:45 p.m., about 13 miles south of where the couple's canoe capsized.

Diamantoni said the body was found about 300 feet from the marina on the York County side of the river.

There were no identifying markers to suggest the body was Brennan, Diamantoni said. It appeared to have been in the water two to four days.

Emergency responders were called to Riverfront Park near Marietta around 3 p.m. Sunday after another boater discovered the Brennans' overturned canoe with a wallet and life jacket inside.

They quickly located Catherine Brennan but a five-hour search of the water and shores yielded no sign of her husband.

Mrs. Brennan told officials she thought her husband was headed to shore but said they lost sight of each other in the rough water.

Neither was wearing a life jacket.

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Officials said Robert Brennan was experienced on the water but said he and his wife had never before been to that particular area of the river in Conoy Township, near the Shocks Mill railroad bridge.