Anderson's family said in a statement Wednesday that they appreciate the support and kindness that friends and fans have shown throughout the Hall of Famer's career and retirement. No further details were released.
The 76-year-old Anderson was inducted into baseball's Hall of Fame in 2000, culminating a major league career that included one nondescript season as a player and an historic run as a manager.
He won 2,194 games as a manager, the third-highest total in major league history trailing Connie Mack and John McGraw. Anderson was the first manager to win World Series titles in both leagues and the only manager to lead two franchises in career wins.
He led Cincinnati's Big Red Machine to World Series wins in 1975-76. He won four National League pennants in Cincinnati from 1970-78, then was fired after consecutive second-place finishes.
Anderson went to the American League and won there, too, directing the Tigers to a World Series title in 1984 and a division title in 1987. He retired after the 1995 season and was added to the Hall of Fame by the Veterans Committee.