The United Nations' special rapporteur on torture says the U.S. military's treatment of an Army intelligence specialist accused of leaking military secrets to WikiLeaks was “cruel and inhuman” and could even be classified as torture.

U.N. expert Juan Mendez this week wrapped up a 14-month investigation of the confinement conditions of Pfc. Bradley Manning, who faces 22 charges, including aiding the enemy, which carries a maximum life sentence in prison.

Mendez said Manning had been held in solitary confinement for 11 months despite not being convicted of a crime. He said if the effects of that treatment on Manning were severe, it could be considered torture.

After his arrest in 2010, Manning spent 11 months confined at the U.S. Marine Corps Base at Quantico, Virginia, where the harsh treatment is alleged to have taken place. He was transferred to Fort Leavenworth, Kansas, last year.

Detention officials said Manning was kept isolated and closely watched because they feared he would hurt himself.

Mendez said in a report last month that he tried without success to get permission from military officials for an unmonitored interview with Manning. He says Manning's treatment has improved since he changed locations.

Manning's release of the diplomatic cables and military reports to WikiLeaks infuriated the international community, often providing blunt and unflattering U.S. views of world leaders' private and public lives.

U.S. officials say WikiLeaks' publication of the stolen document put lives in danger, threatened national security and undermined American efforts to work with other countries.