U.S. Defense Secretary Robert Gates on Friday said the secretary of the Army, Francis Harvey, resigned after reports troops wounded in Iraq and Afghanistan were receiving substandard medical treatment at the Army's top hospital, Reuters reported. Harvey's resignation came a day after the head of the Walter Reed Medical Center was fired. "I am disappointed that some in the Army have not adequately appreciated the seriousness of the situation pertaining to outpatient care at Walter Reed," Gates said. "Some have shown too much defensiveness and have not shown enough focus on digging into and addressing the problems." Gates said a new permanent head of the medical center would be announced today. That comes as the Bush administration faces questions over a decision to put Army surgeon-general Lt. Gen. Kevin Kiley, a former commander of Walter Reed, in temporary charge of at the hospital.