Federal Reserve under attack by hacker spies

The Federal Reserve has been under constant attack by hackers since at least 2011, including four attempts it labels as "espionage," according to records obtained by CNNMoney.

While it's unclear if hackers have been successful, records list more than 50 incidents labeled as either "unauthorized access" or "information disclosure."

"As with other government agencies, the Federal Reserve is a target for cyberattacks," federal officials said in a statement. "However, our security program and processes for detecting and countering attacks are robust and our critical operations have never been affected."

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