The decision by a panel of the federal appeals court in Washington, D.C., undoes an attempt to wrap up more than two decades of military prosecution beset by legal and logistical troubles.

A US appeals court on Friday scrapped 9/11 mastermind Khalid Sheikh Mohammed's plea agreement that would have taken the death penalty off the table and helped conclude the long-running legal saga surrounding his case.

The D.C. Circuit Court of Appeals concluded that the plea agreements agreed to by a Pentagon official overseeing military commission proceedings against Khalid Sheikh Mohammed, Wa