(Washington, DC)  --  Homeland Security Secretary Janet Napolitano is resigning her post to become president of the University of California system.  Napolitano has been running Homeland Security since the beginning of President Obama's tenure.  In a statement, the former Arizona governor praised the men and women of the Homeland Security Department.  She said they have helped "minimize threats of all kinds to the American public."  Napolitano has also been a strong advocate for comprehensive immigration reform and enhanced cybersecurity. 

She'll remain on the job until early September.  White House spokesman Jay Carney said the President has not chosen a successor.