The Russian government hack into multiple Democratic computer networks was broader than initially reported as officials confirmed Wednesday that the personal email accounts of more than 100 party officials were breached.
The series of cyber attacks targeting Democratic organizations and staff have primarily infiltrated the private email accounts of Clinton campaign staff and party operatives.
FBI agents have begun notifying Democratic staff whose personal accounts were breached by the Russians as the agency widens its investigation.
Investigators confirmed nearly two weeks ago that Russians breached the Democratic Congressional Campaign Committee, the campaign arm for House Democrats, in an incident that paralleled the earlier cyber attack on the Democratic National Committee.
Democrats involved in the FBI probe said the agency now believes the hack may have extended to the Democratic Governors Association.
Intelligence officials suspect that Russian government hackers were responsible for the DNC cyber attack that led to troves of stolen documents being released by WikiLeaks last month. The leak forced the resignation of former DNC chair Debbie Wasserman Schultz because of emails suggesting the party favored Hillary Clinton over Sen. Bernie Sanders (I., Vt.) during the Democratic primary.
Russia has denied involvement in the attacks.
"We don’t see the point any more in repeating yet again that this is silliness," Kremlin spokesman Dmitry Peskov told Reuters in July.
President Obama previously warned that it was possible Russian hackers were attempting to sway the U.S. election. Clinton’s campaign has maintained that the Kremlin is behind the breaches in an attempt to help Republican presidential nominee Donald Trump.
U.S. authorities remain uncertain of Russian motives, according to a federal law enforcement official.
Trump received a firestorm of criticism earlier this month after he called on Russia to hack and release Clinton’s 30,000 deleted State Department emails.