Police in St. Louis, Missouri, say rock 'n' roll legend Chuck Berry has died at age 90. Berry was an American music legend, a pioneer of the rock 'n' roll style, which blended rhythm and blues with pop music in a blend that became synonymous with the developing culture of American teenagers in the 1950s. Police in St. Charles County, Missouri, announced in a Facebook post Saturday that they had responded to a medical emergency at a local home. After unsuccessfully trying to revive him, officials pronounced Berry dead. Berry's death was announced using his full name Charles Edward Anderson Berry Sr. Police say the family has requested privacy.