The director of the Department of Homeland Security's U.S. Computer Emergency Readiness Team (US-CERT) has resigned, several media outlets reported over the weekend.

Mischel Kwon is leaving the post after less than a year, and will soon take a job in the private sector, The Washington Post reports. The newspaper cited anonymous sources who said she was "frustrated by bureaucratic obstacles and a lack of authority to fulfill her mission." She was the fourth director of U.S.-CERT in the last five years.

U.S.-CERT was established in 2003 as an arm of the National Cyber Security Division within the Department of Homeland Security (DHS) in order to protect the nation's Internet infrastructure, including .gov domains.

Kwon's departure is the latest blow to the top of the Obama administration's cyber-security hierarchy. Melissa Hathaway, the president's acting senior director for cyber-space, resigned last week -- only three months after she completed a comprehensive 60-day review of the federal government's cyber-security readiness.

Federal News Radio host Chris Dorobek blogged Monday that there is buzz from within the cyber-security community about the reasons for those resignations.

Kwon and Hathaway are just the latest to leave. Rod Beckstrom resigned in March from his post as director of the National Cyber Security Center (another DHS office) because of what he said was a lack of support and resources. He wrote in his resignation letter that it was "bad strategy' for the National Security Agency to have a role in protecting the federal government's computer systems.

Matt Williams  |  Associate Editor