DOWNSVILLE, Md. — Authorities believe a boating accident near Dam 4 of the Potomac River led to a Keedysville, Maryland couple’s death over the weekend.

Maryland Natural Resources Police believe David King, 63, and Susan King, 62, went over the dam in their bass boat shortly after launching at Big Slackwater, a few miles upstream.

“Their truck and trailer were found up from dam 4 and then they and their boat were found below dam 4,” Maryland Natural Resources Police Sgt. Katherine Medellin told MetroNews affiliate WEPM.

The search began at around 10:30 Sunday morning after authorities received a call of an overturned boat. Nobody reported the couple as missing.

“They were seen launching their boat on Saturday around 1 in the afternoon,” said Sgt. Medellin. “We got a call yesterday (Sunday) morning about a boat overturned below dam 4 with some damage to it. That, in turn, started the wheel turning for our investigation and then we put two and two together.”

The Potomac River marks the Maryland/West Virginia line, with Berkeley County on the southern edge of the river and Washington County, Maryland to the north.

The incident remains under investigation.