The chief of the agency tasked with shielding U.S. government networks from cyber attacks has stepped down following a string of embarrassing data breaches by hackers.
Randy Vickers, head of the U.S. Computer Emergency Readiness Team, resigned Friday, according to an email obtained by The Huffington Post.
Lee Rock, the deputy director for US-CERT, will serve as interim acting director of the agency, which serves as the cybersecurity arm of the Department of Homeland Security.
"We are confident that our organization will continue its strong performance under his leadership," according to the email from Roberta Stempfley, acting assistant secretary for cybersecurity and communications.
Vickers' resignation comes as the Obama administration proposes giving DHS greater oversight over computer networks in both the public and private sector and as hackers continue to expose widespread gaps in government cybersecurity.
Cyber attacks against federal government networks spiked about 40 percent last year, from about 30,000 in 2009 to nearly 42,000 in 2010, according to a report this spring by the Office of Management and Budget.
US-CERT is also tasked with reporting cyber threats against federal computer systems that use the .gov domain.
"It is pretty big news because Randy set the vision [of government cybersecurity] for quite awhile," said Anup Ghosh, a former Pentagon cyber scientist and founder of the cybersecurity firm Invincea Inc.
But under his leadership, hacker groups have "made a public mockery" of government networks, Ghosh said. "A lot of us are wondering now what's going on and how they are going to fill his shoes."