Some 50 prisoners at Guantanamo Bay (search) have declared they are on a hunger strike, a Pentagon spokesman said Thursday.

They went on strike three days ago, spokesman Bryan Whitman (search) said. Some have already begun eating again, he said. The spokesman said he did not know why they went on strike and said the health of the striking detainees is being monitored.

The Pentagon's (search) version of this incident contrasted somewhat from the accounts of two Afghans released from the facility for terrorist suspects earlier this week. On Wednesday, they claimed that more than about 180 Afghans were on a hunger strike to protest alleged mistreatment at the facility at a U.S. military base in Cuba.

Habir Russol and Moheb Ullah Borekzai, who said they left the prison camp on Cuba on Monday and were flown to Afghanistan before being freed, said they did not participate in the hunger strike. They did not say how they knew others were refusing to eat.

Russol said 180 Afghan prisoners "are not eating or drinking." He and Borekzai estimated the men were in the 14th or 15th day of their fast.

Borekzai later told The Associated Press the detainees were protesting because "some of these people say they were mistreated during interrogation. Some say they are innocent."

"They are protesting that they have been in jail nearly four years and they want to be released," he said.

Neil Koslowe, a Washington-based lawyer for 12 detainees from Kuwait, said several inmates told him during a June 20-24 visit to Guantanamo that there was a "widespread" hunger strike over the amount and quality of their drinking water.

The two Afghans released this week said they had been accused of being members of the former Taliban regime, but both said they were innocent. Neither said how long they had been detained.

The Pentagon also announced Wednesday that seven Guantanamo detainees had been released and an eighth transferred to the custody a foreign government. In addition to the two released Afghans, three Saudi Arabians, a Jordanian and a Sudanese were freed, it said.

The three Saudis, who were not identified, were handed over to Saudi security, the official Saudi Press Agency said in Riyadh. It did not specify whether the three were detained for questioning, saying only that "the regular procedures will be applied accordingly."

In addition, a Moroccan was transferred to control of the government of Spain, U.S. officials said. The Pentagon did not identify the detainees. The Moroccan was identified earlier this week in Spain as Lahcen Ikassrien, who had been charged there for his links to an al-Qaida cell.

The transfers leave about 510 prisoners at Guantanamo.