CNNMoney reported that the Fed's March meeting minutes were then released Wednesday morning, to allow the public to catch up with the early mailing, which was said to have been a human error.
The early release was "entirely accidental," a Fed spokesman said.
The minutes are generally released at 2 p.m., on Wednesday. They were released at 9 a.m. instead to make up for the blunder.
The meeting minutes are mostly predictable, as the policy decisions from a meeting are released as soon as the meeting ends and reporters can comb through speeches to predict where individual decision makers stood on various issues.
The March meeting minutes revealed that some policymakers are concerned that the $85 billion per month in asset purchases the Fed is undertaking could trigger inflation by making too much money available.
The Fed is buying $45 billion in Treasury securities and $40 billion in mortgage-backed securities each month.
Other policymakers said the program known as quantitative easing should continue until 2014.
The minutes also show that some on the Open Market Committee predicted the pace of hiring would slow down.
Fed Chairman Ben Bernanke said he was looking for a possible "spring slump," in job creation. Atlanta Fed President Dennis Lockhart said he was anticipating a mid-year "swoon."