Watergate special prosecutor Archibald Cox expressed "extreme interest" in a 1970s criminal investigation of Yankees owner George Steinbrenner for illegal campaign contributions. Then-FBI Director Clarence M. Kelley relayed Cox's concern in a memo on Aug. 16, 1973, to the bureau's Cleveland office, according to documents released Thursday. The FBI felt agents needed to make sure the probe received "the same, immediate and preferred handling" as other criminal cases then growing from the Watergate scandal. The memos were included in a 400-page release of Steinbrenner's FBI file. Most of the material focused on the Watergate-era federal probe that led to the shipbuilding magnate's 1974 conviction for illegal contributions to disgraced President Richard M. Nixon.