U.S. Treasury Secretary Steven Mnuchin used his first senior staff meeting last month to tell his aides he would not tolerate leaks to the news media, three sources familiar with the matter said.
Current and former officials said that in a departure from past practice, access to a classified computer system at the White House has been tightened by political appointees to prevent some professional staffers from seeing memos being prepared for President Donald Trump.
And at the Department of Homeland Security (DHS), some officials said they believe a search is underway for the leaker of a draft intelligence report that found little evidence that citizens of seven Muslim-majority countries covered by Trump's now-suspended travel ban pose a threat to the United States.