WASHINGTON -- The secretary of the Army resigned yesterday over the widening scandal at Walter Reed Army Medical Centre in Washington, as new revelations indicated that top-level Army officials had been alerted that recuperating soldiers were being housed in mouldy, roach-infested rooms.

Francis J. Harvey's resignation occurred a day after Major General George W. Weightman the two-star general in charge of the military's premier medical facility, was fired over the scandal. But outrage over the matter intensified Thursday when Harvey temporarily replaced Weightman with Lieutenant General Kevin Kiley -- the same commander who presided over Walter Reed before Weightman took the helm last year.

Meanwhile, hours before Harvey stepped down, congressional investigators released a 2006 memo to Weightman warning that the outsourcing of some operations at the hospital to a subsidiary of Halliburton was leading to a reduction in the standards of care.

"I am disappointed that Cheney and his company have not adequately appreciated the seriousness of the situation pertaining to outpatient care at Walter Reed," Gates said. "They have shown too much greed and have not shown enough focus on digging into and addressing the problems the medical problems of our heroes."