Flanagan had been upset about financial issues, police said Thursday.
Flanagan's wife, Alex, who was out of town, had sent a neighbor to their house in the 15000 block of York Road in Sparks on Wednesday afternoon when she didn't hear from her husband. According to police, Alex had last spoken to an upset Flanagan around 1 a.m. and was concerned when he failed to call her the following day. The neighbor, unable to find Flanagan, called 911.
Baltimore County police found Flanagan's body on trail about 250 feet behind his home around 4:30 p.m.
Police confirmed Thursday that Flanagan, 59, appeared to have shot himself in the face, making identification difficult and causing official confirmation of his death to be delayed. Flanagan did not leave a note, police said.
The Flanagan family released a short statement Thursday through the Orioles.
"We thank you for your support and kind words at this difficult time. Thank you for respecting our privacy as we grieve," the statement said, adding that a private memorial would be held but did not provide details.
Word of Flanagan's death spread quickly in baseball circles, with former teammates and current Orioles players offering tributes.
"It's just shock right now," said former Orioles catcher Rick Dempsey. "I know everybody that played with him loved him to death. He was the backbone of that pitching staff."
Flanagan, who was in his second year as a color analyst for the Mid-Atlantic Sports Network, spent more than 30 years with the Orioles as a player, coach, front office executive and broadcaster.
The Orioles first confirmed Flanagan's death Wednesday night, issuing a statement from owner Peter Angelos.
"In over a quarter century with the organization, Flanny became an integral part of the Orioles family, for his accomplishments both on and off the field," Angelos said. His loss will be felt deeply and profoundly by all of us with the ballclub and by Orioles fans everywhere who admired him. On behalf of the club, I extend my condolences to his wife, Alex; and daughters Kerry, Kathryn and Kendall."
"Mike was such a unique guy, talented, witty, funny," said Hall of Fame pitcherJim Palmer. "You are not ready to lose someone like Mike Flanagan. But on the other side, I feel lucky to be part of the organization and have had him as a friend and a confidant and buddy, and see all facets of him."
Cal Ripken Jr. said in a statement: "I am so sorry to hear about Mike's passing. He was a good friend and teammate and our thoughts are with Alex and his family. Mike was an Oriole through and through and he will be sorely missed by family, friends and fans. This is a sad day."
At Flanagan's home Wednesday night, a light was on inside the home and a police car blocked the driveway, letting two vehicles enter the property. Property records show Flanagan, a New Hampshire native, and his wife, Alex, purchased the 10.5-acre property in 1997 for $525,000.
Selected by the Orioles in the 1973 amateur draft, Flanagan went on to pitch 18 major league seasons, including parts of 15 with the Orioles. He was a key member of the 1983 world champions, going 12-4 with a 3.30 ERA in the regular season and winning Game 3 of the American League Championship Series against theChicago White Sox.
The left-hander won 141 games in his Orioles career, including an American League-leading 23 in 1979, when the Orioles lost the World Series to the Pittsburgh Pirates in seven games.
Flanagan won the American League Cy Young Award that year as the league's top pitcher and finished sixth in Most Valuable Player voting. His lone All-Star season was in 1978, when he won 19 games in 40 starts, tied for the most in the league.
The Orioles traded him to the Toronto Blue Jays in 1987, for pitchers Oswaldo Peraza and Jose Mesa. Flanagan was the last Orioles pitcher to pitch at Memorial Stadium, entering the game against the Detroit Tigers on Oct. 6, 1991, with one out in the ninth inning. He struck out Dave Bergman and Travis Fryman. He returned to the Orioles in 1991 as a 39-year-old free agent, spending the last two seasons of his playing career pitching in relief.
After being named to the Orioles Hall of Fame in 1994, Flanagan served as the team's pitching coach twice, in 1995 and 1998.
He spent 1996-1997 and 1999-2002 broadcasting Orioles games before becoming the club's executive vice president after the 2005 season, a role he held until his contract expired at the end of 2008.
Orioles managerBuck Showalter said he got word in the middle of Wednesday night's game.
"Mike made a point of making me feel welcomed from Day One. I always looked forward to him coming in and sitting down and drinking coffee with me, and not only talking about baseball but talking about life," Showalter said. "He was a passionate man about the Orioles and family, and he impacted a lot of people's lives, not just by the way he pitched but [as] someone our organization has always been proud of not only for the way he pitched but the way he treated people."
Orioles pitcherJeremy Guthrie, who wore Flanagan's uniform number 46, said, "I think he was so close to so many people in this organization and he has touched the lives of countless thousands of people in the Baltimore community and in the baseball world."
Baltimore Sun reporters Luke Broadwater and Jessica Anderson contributed to this article.
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