The Marine who built and ran the Guantanamo Bay prison says the U.S. lost the "moral high ground" by its treatment of prisoners and the facility should be closed.

Marine Maj. Gen. Michael Lehnert spoke to reporters Thursday at Camp Pendleton in San Diego County.

Lehnert commands seven West Coast bases but he's retiring Tuesday. In 2002, he was tasked with building prison cells at the U.S. Navy base in Cuba to hold enemy detainees.

Lehnert says he wasn't in charge of interrogating prisoners and disagreed with other officers about the use of harsh methods. Lehnert says by the end of his 100 days at Guantanamo, he believed the prison should be closed.

But he says the 200 or so prisoners still there should not be sent to stateside military bases.