Guantanamo Bay detention center's top commander was fired “over a loss of confidence” in his leadership, officials said Sunday.

U.S. Navy Rear Adm. John Ring was relieved of duty and will be replaced by Adm. Craig Faller, the U.S. Southern Command said in a statement.

U.S. Navy Adm. Craig Faller

Command spokeswoman Amanda Azubuike said the firing occurred after an investigation that began in March.

“The vast majority of commanders complete their assigned tours with distinction,” she said in an email to NBC News. “When they fall short, we hold our leaders accountable.”

U.S. Army Brig. Gen. John Hussey was designated acting commander of the center, the command said in the statement.

Hundreds of alleged terrorists have been held at Guantanamo since it opened in 2002, though no new detainees have arrived since 2008. In November, NBC News reported that 40 still remained, including a 71-year-old.

Ring became commander of Guantanamo last April. In an interview last year with NBC News, he described parts of the detention camp as “falling into the ground and deteriorating rapidly.”

He said he wasn’t sure if he would receive funding to prepare for the possible arrival of new detainees or to adequately care for the aging population already there.

"I'm the innkeeper," Ring said at the time. "I don't make laws. People in D.C. tell me when people are going away, when people may be coming in, and my job is to keep these folks comfortable, safe."

The Southern Command said Sunday that Ring's departure "will not interrupt the safe, humane, legal care and custody provided" to its detainees.