Fifteen Saudi Arabians have arrived home after being released from the United States military detention camp at Guantanamo Bay in Cuba.
About 460 detainees remain at Guantanamo, 100 of them Saudis
Relatives of the freed men gathered at Riyadh airport to meet them.
State Department spokesman Sean McCormack said an understanding had been reached with the Saudi government over their release.
About 460 detainees are held at Guantanamo, which opened after the US-led invasion of Afghanistan in 2001.
Detainees are being held without charge or trial.
Mr McCormack said: "We were able to assure ourselves that if these people were returned to Saudi Arabia that they wouldn't be tortured and they would be treated humanely."
Saudi Arabia's Interior Minister Prince Nayef said the kingdom was trying to secure the release and return of the remaining Saudi detainees at Guantanamo Bay.
He said that the 15 men "will be made subject to the country's laws", comments that suggest the men may be put on trial.
Eight Saudis have previously been released from Guantanamo Bay, but jailed back home.
At least five of them were freed by Saudi Arabia last year after they completed their jail terms.
It is believed that about 100 of the detainees at Guantanamo Bay are Saudi nationals.
Family members of the returnees gathered at King Khaled airport to meet the plane, while reporters were kept away from the scene.