FBI Lectures Trump and Clinton Staffers on Avoiding Foreign Spies

The FBI on Wednesday warned staff members working on the Donald Trump and Hillary Clinton presidential campaigns that they may be targets for foreign intelligence agents.

Any new person a staffer meets in Washington DC or elsewhere may be a spy, the agency said, during security briefings held in the building shared by rival Trump and Clinton campaign teams, sources say.

The FBI believes that protecting US secrets is more important than ever, especially now that foreign actors have increased efforts to influence the approaching elections. Campaign staff, according to the agency, should remember that foreign states may use human source networks to obtain sensitive data.

The security sessions, which lasted for about an hour, were described as "voluntary awareness briefings" and a "routine procedure," not prompted by a known threat. However, the FBI official acknowledged their suspicion that foreign intelligence seeks to sway the US election, particularly alleged espionage efforts by Russian black hat hackers.

In July, WikiLeaks published almost 20,000 pages of hacked emails that revealed top DNC officials deliberately worked to obstruct Democratic presidential hopeful Bernie Sanders' campaign, in order to boost his then-rival Hillary Clinton's chances of becoming the party's presidential nominee.

After the emails were leaked, Clinton claimed that Russian hackers were responsible, as the leak was seen to benefit GOP presidential nominee Donald Trump. A top US intelligence official, who wished to remain anonymous, said recently that it is "not surprising" that Russia is trying to undermine the US political process, as it may be Russian President Vladimir Putin's response to efforts by the NSA to "influence political developments in Russia."

Both the Kremlin and the Russian Foreign Ministry have refuted the claims of Moscow's involvement in the hacking activities.