The head of cybersecurity efforts at the US Department of Homeland Security (DHS) has resigned this week, reportedly giving only one day's notice.

Amit Yoran, director of the DHS national cyber security division since September 2003, gave notice on Wednesday that he would leave the job the very next day, according to an Associated Press news report. Yoran, former vice president of worldwide managed security services at Symantec, resigned because of a lack of priority for cybersecurity within DHS, according to AP.

A DHS spokeswoman on Friday confirmed Yoran's resignation. The agency viewed Yoran's service as a "valuable contribution" to cybersecurity, said Katy Mynster, a DHS spokeswoman.

Asked to comment on reports that Yoran resigned over a lack of priority for cybersecurity, Mynster said she believed he quit for other professional reasons. "Cybersecurity has been and will remain a priority for DHS," she said.

Yoran is the second cybersecurity chief to resign in less than two years. In January 2003, Richard Clarke resigned, citing frustration with the Bush administration's lack of progress in cybersecurity. Just last week, Yoran appeared at a National Cyber Security Alliance press conference to promote October as National Cyber Security Awareness Month. Because of collaboration between private business and the government, "cyberspace is becoming a safer place", he said at the time.

Software executives said they are disappointed Yoran felt he had to resign. His resignation could be a setback in DHS efforts to improve cybersecurity, said Douglas Goodall, head of security company RedSiren. Yoran's job - dealing with the "politics and competing priorities" in DHS - was a tough one, Goodall said.

The White House released a National Strategy to Secure Cyberspace in February 2003, and without a strong leader at DHS, that report could gather dust, Goodall said. "Our fear, our concern, is in fact this could create a delay in turning a strategy into action," he added. "It's very important to put a strong leader in quickly who can carry this forward."

The Information Technology Association of America issued a statement saying Yoran's resignation was a "disappointing setback". The group called for the cybersecurity chief position to be elevated in the agency's hierarchy.