Updated

Rescue crews searched the Chesapeake Bay on Sunday for a prominent publisher and former diplomat whose sailboat was found sitting on the water with its engine running.

Philip Merrill, 72, an experienced sailor, had been sailing alone in breezy weather Saturday, said Tom Marquardt, executive editor of The [Annapolis] Capital, one of seven periodicals Merrill publishes.

Skies were clear with winds gusting up to 25 mph — "a condition that would probably be difficult for a single sailor alone," Chaney said.

Two boaters found Merrill's boat near Plum Point, about 25 miles south of Annapolis, and called police, officials said

State and federal agencies searched 100 square miles of the bay with aircraft and boats. But rescue crews think Merrill fell overboard since his wallet was found on board and there was no damage to the boat, officials said.

"As time goes by, chances of survival are less and less," Chaney said.

Merrill "has been an avid yachtsman since he first learned to sail at age 7. He has been actively cruising the Chesapeake since 1958," his wife, Eleanor, and children said in a statement issued by Marquardt.

"If there was anyone who could captain a boat competently alone, it was Phil. ... He just couldn't resist a sunny day with the wind at his back."

State and federal agencies joined the search. The Coast Guard sent both aircraft and boats, and was operating under the assumption that Merrill fell overboard, said Senior Chief Steve Carleton.

Merrill is chairman of the board of Annapolis-based Capital-Gazette Communications Inc., which publishes The Washingtonian magazine, The Capital and five other Maryland newspapers.

Merrill took leave from publishing in December 2002 to be president and chairman of the Export-Import Bank of the United States. His term expired in July 2005.

He served as assistant secretary-general of NATO in Brussels from 1990 to 1992 and from 1983 to 1990 he served on the Department of Defense Policy Board. From 1981 to 1983, he was counselor to the undersecretary of defense for policy. In 1988, the secretary of defense awarded him the Medal for Distinguished Service, the highest civilian honor given by the department.

Merrill has represented the United States in negotiations on the Law of the Sea Conference, the International Telecommunications Union and various disarmament and exchange agreements with the former Soviet Union. He is a former special assistant to the deputy secretary of state and has worked in the White House on national security affairs.

The college of journalism at the University of Maryland was named for him, as was the headquarters of the Chesapeake Bay Foundation — both after multimillion-dollar donations.