Donald Trump said he would demand that the journalist who first reported the rescue of a U.S. airman in Iran reveal their source and threatened jail time if they refused.

His comments marked a sharp escalation in criticism of the media, which he accused of harming national security by publishing sensitive information.

Trump said the disclosure could have endangered ongoing rescue efforts, though the second airman was eventually recovered.

Several news outlets had reported the rescue shortly after it occurred, but it was unclear which one he was referring to, Reuters has reported.

The White House did not clarify his remarks, while administration officials have increasingly criticized media coverage of the U.S.-Iran conflict.