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On Thursday, self-proclaimed "hactivists" with reported links to the Russian government published about 18 months of emails stolen from the Gmail account of a low-level Democratic operative, revealing mostly routine, detailed information about the scheduled movements of Vice President Joe Biden, Hillary Clinton, and First Lady Michelle Obama at past campaign and police events. The hacked documents also contain a purported scan of Michelle Obama's passport, the names and cellphone numbers of Secret Service agents, and the Social Security numbers of some Clinton campaign donors.

The hacked emails of 22-year-old Ian Mellul, essentially a White House volunteer, were posted by DC Leaks, a new site that also posted the hacked emails of former Secretary of State Colin Powell. Security experts and U.S. officials say the group is a front for a broad Russian government effort to sway or disrupt the U.S. presidential election, though DC Leaks claims to be Americans pledging to "publish a large amount of emails from top-ranking officials and their influence agents all over the world." Mellul, The New York Times notes, "hardly fits either description. His low-level job ranks just above that of an intern."

Attorney General Loretta Lynch said at a news conference that "we're aware of those media reports, and it is something we're looking into," and Secret Service spokeswoman Cathy L. Milhoan said it is also "aware of the alleged email hacking of a White House staffer, adding, "Obviously the Secret Service is concerned any time unauthorized information that might pertain to one of the individuals we protect, or our operations, is allegedly disclosed."

The leaks have almost exclusively targeted Clinton and other Democrats, and on Thursday, Rep. Adam Schiff (D-Calif.) and Sen. Dianne Feinstein (D-Calif.), the top two Democrats on congressional intelligence committees, directly accused Russia of "making a serious and concerted effort to influence the U.S. election," adding bluntly: "We believe that orders for the Russian intelligence agencies to conduct such actions could come only from very senior levels of the Russian government."