The Obama Administration named an interim US Customs and Border Protection Chief, within hours of the current one's resignation.

FOX News Radio's Jessica Rosenthal has more in our ongoing series on national security:

CBP Commissioner Alan Bersin says he's resigning at the end of the month. In a statement Bersin says serving as Commissioner has been one of the most rewarding experiences. Adding he's proud to have strengthened border security and the ability to prevent terror threats.

Homeland Security Secretary Janet Napolitano quickly named CBP Deputy Commissioner David Aguilar as interim replacement - Bersin himself was named as Commissioner only in a recess appointment and after his Senate committee hearing admitted he had made mistakes in his tax filings on domestic help he'd once hired.

Jessica Rosenthal, FOX News Radio.