The PMOI released images showing the protest at Camp Ashraf in July
A group of 36 Iranian opposition members have been freed after nearly three months in custody in Iraq.
The men were returned to Camp Ashraf in northern Iraq, where more than 3,000 People's Mujahideen of Iran (PMOI)members have been confined since 2003.
A spokeswoman for the group told the BBC they had been tortured in custody and were now being treated in hospital.
The men were detained by Iraqi police in July during a raid on the camp in which seven PMOI members were killed.
The PMOI, also known as Mojahedin-e Khalq, is considered a terrorist group by the US and Iran.
It was removed from the EU and UK's lists of banned organisations this year after lengthy legal battles.
Iraq in charge
The PMOI set up a base in Iraq in the 1980s and were welcomed by then-President Saddam Hussein, who was fighting a war against Iran.
He armed the group's military wing, the National Liberation Army of Iran, which then fought alongside Iraqi troops.
Relatives and friends of those at Camp Ashraf have been on hunger strike
The camp was surrounded and disarmed by US soldiers following the US-led invasion of Iraq in 2003. But since then, relations between Iran and Iraq have improved and the government in Baghdad has repeatedly vowed to close the camp.
Iraqi forces took over its security from the US earlier this year, and the top US military commander in the country said he had received no advance warning of the move.
Relatives and friends of those at Camp Ashraf have been demonstrating outside the US Embassy in London since July, calling on the US to take back responsibility. Several are on hunger strike.