Bloomberg News is apologizing for a premature story written last week about the prisoner exchange involving the United States and Russia and says it has disciplined the journalists involved.

Bloomberg News apologized Monday for prematurely publishing a story last week that revealed a prisoner exchange involving the United States and Russia and said it had disciplined the employees involved.

The story moved nearly four hours before an embargo on the exchange was lifted by the White House.

John Micklethwait, Bloomberg’s editor-in-chief, said in a memo to staff Monday that the story represented a clear violation of ethical standards. Bloomberg would not say how many employees were disciplined and did not identify them.