The body of an elderly woman believed to be the victim of a plane crash in the Chesapeake Bay has been recovered, authorities reported Monday.

The body has not been positively identified, but police believe it is Mary L. Lagerquist, 78, of Sequim, Wash. Her body was found about 9 a.m. in the waters off the southern point of Smith Island.

Lagerquist’s son, Lanson C. Ross III, 48, of Fort Washington in Prince George’s County, was piloting the single-engine plane when it crashed Sunday.

Police said that Ross and Lagerquist left Hyde Field in Clinton on Sunday to visit Tangier Island. It was on the return trip that Ross began experiencing trouble. He radioed the Patuxent River Naval Air Station and said he would try to reach Smith Island.

Ross told investigators that the plane lost power on the way to Smith Island, but said both he and his mother were able to get out of the plane after it crashed and before it sank.

“Ross said after about a mile of swimming in rough water with waves three to five feet high, his mother passed away,” Greg Shipley, a spokesman with the Maryland State Police, said in a news release. “Ross continued on and was able to reach the island.”

Ross reached the island around 8 p.m. Sunday. He was taken to Peninsula Regional Medical Center in Salisbury for non-life-threatening injuries and released overnight, police said.

The U.S. Coast Guard, Maryland Natural Resources Police and Virginia Marine Police conducted the search for Lagerquist’s body after the crash.

The airplane has not been located. The National Transportation Safety Board and the Federal Aviation Administration will be responsible for investigating the cause of the crash, police said.