WASHINGTON — Military prosecutors have refiled capital charges against Khalid Sheik Mohammed and four co-defendants accused of orchestrating the attacks of Sept. 11, 2001, restarting a process that the Obama administration had halted as part of its failed effort to close the military detention center at Guantanamo Bay, Cuba.

Charges against the five men were withdrawn without prejudice and dismissed in January 2010 in anticipation of a federal trial in New York City. Bipartisan opposition scuttled that plan, and Attorney General Eric Holder announced in April that the defendants would be returned to Guantanamo Bay to face a military tribunal.

Although the five defendants were first charged in 2008, and numerous pretrial hearings were held before the case was stopped, it must begin again with a fresh arraignment. Under military law, the defendants must first be referred for trial by a Pentagon official known as the convening authority, but that step seems certain in this case.

Among the first issues likely to be considered again is the defendants’ wish to represent themselves. They are each entitled to a military attorney and “learned counsel,” a lawyer with experience in death penalty cases.