The Cape Cod District Attorney's Office has identified the man whose body was found on Sunday afternoon in the Cape Cod Canal as 54-year-old Scott Allen Graichen of New Hampshire.

Officials said the matter remains under investigation and no more information is available at this time.

The Coast Guard suspended the massive search for Graichen, which included assistance from Wareham authorities, Sunday at approximately 12:30 p.m.

A boat crew from Coast Guard Station Cape Cod Canal located his body unresponsive in the Cape Cod Canal, returned to shore, and transferred authority to Massachusetts Environmental Police and Sandwich Fire Department who pronounced him dead.

The nearly 22-hour search covered about 400 nautical miles, and included all of Buzzards Bay and the west entrance of Cape Cod Canal. Coast Guard Station Cape Cod Canal, Coast Guard Station Woods Hole, Coast Guard Air Station Cape Cod, the Coast Guard Cutter Ocracoke, the Buzzards Bay Task Force, Massachusetts Environmental Police, Army Corps of Engineers, and local good Samaritans all joined the search effort.

“We maximized our efforts throughout the search, always with the hope of locating the man alive,” said Capt. Richard Schultz, commander of Sector Southeastern New England. “When we lose a fellow mariner, it is felt across the entire marine community.”

Wareham Harbormaster Marine Units 1 and 2 participated in the search. It was launched Saturday afternoon when a 33-foot power boat was located operating without anyone onboard near the Buzzards Bay entrance of the Cape Cod Canal.

According to Wareham Harbormaster Garry Buckminster, Buzzards Bay Marine Task Force sent out a message alerting all rescue units in the area of the empty boat, which was running in circles.

The unnamed and unregistered boat was brought ashore in Onset.

The Mattapoisett Fire Department, New Bedford Fire Department, Marion Harbormaster, Marion Fire Department and Massachusetts Environmental Police were involved.

Buckminster said the sea conditions during the search were unfavorable.

“It’s really rough out,” said Buckminster. “The canal is probably treacherous with the wind.”