Without identifying the dismissed officer, Esperon said the military had already referred the matter to the Philippine National Police (PNP) for investigation and for the corresponding legal action.
Aside from the PNP, the Department of Justice placed the dismissed officer, with the rank of major, under investigation since he is already a civilian.
"That officer who held a press conference is a discharged major, I will not say from which branch of service. He was discharged by the Efficiency and Separation Board (ESB) in 2003 for having defrauded the government of a sizable amount," Esperon told reporters late Thursday night.
Early this week, members of a group calling themselves NOU declared during a clandestine television interview that they will resign en masse due to the countrys worsening political problems brought about by questions regarding the legitimacy of the Arroyo administration.
The interview came a day before the majority members of the House of Representatives were about to junk the impeachment complaints filed by the political opposition against President Arroyo.
"Is he really a nationalist? Or does he want to get even after he was discharged from the service due to embezzlement?" Esperon said.
A well-placed source identified the discharged officer as Marine Maj. Josebel Pates. The source said the military identified Pates through his voice.
Marines spokesman Lt. Col. Ariel Caculitan refused to confirm or deny if Pates was the alleged NOU spokesman, but confirmed that Pates was discharged by the Navy ESB in 2003 for alleged violation of Article of War 96 (conduct unbecoming an officer and a gentleman).