PHILADELPHIA (CNN) — The FBI on Monday confirmed they are investigating a hack into the Democratic National Committee, the first acknowledgment from the agency that they are probing the incident.

Fallout over the emails led DNC Chairwoman Debbie Wasserman Schultz to announce her resignation Sunday.

“The FBI is investigating a cyber intrusion involving the DNC and are working to determine the nature and scope of the matter,” the agency said in a statement. “A compromise of this nature is something we take very seriously, and the FBI will continue to investigate and hold accountable those who pose a threat in cyberspace.”

US officials briefed on the investigations told CNN Sunday that the suspected Russian hack is part of a wave of Russian cyber attacks aimed at political organizations and academic think tanks in Washington.

The-CNN-Wire ™ & © 2016 Cable News Network, Inc., a Time Warner Company. All rights reserved.