The People's Mojahedin (PMOI) is an Iranian opposition movement in exile that has been battling the Tehran government since the 1960s.
On Tuesday Iranian President Hassan Rouhani asked France to demand action against a group he accused of fomenting protests which rocked the country in recent days.
He was apparently referring to the PMOI, also known as the Mojahedin-e-Khalq, which for years was designated a "terrorist" group by the West.
- Emergence in Iran -
The PMOI was founded in 1965 after a split within the nationalist Liberation Movement of Iran (LMI), led by Mehdi Bazargan, who became the first prime minister after the Iranian revolution.
It was founded to fight Iran's royalist regime and most of its founding members died in the prisons of Shah Mohammad Reza Pahlavi.
With Marxist leanings and describing itself as belonging to "democratic and secular Islam," the group has subsequently sought to overthrow the country's current Islamic republic.
After a brief period as a legal organisation with the Islamic revolution of 1979, the group was outlawed by Iran in 1981 after a severe crackdown on one of its demonstrations, which it says was peaceful.
In June of that year, a bomb attack in Iran which killed 74 people including Ayatollah Beheshti, the regime's number two, was blamed on the Mojahedin by the authorities. The group never claimed the attack, while it had claimed others.
- Driven into exile -
The Mojahedin took on the regime, which responded with repression, with thousands of its members being killed. Those who survived were chased from Iran.
They found refuge throughout the world, particularly in France, where leader Massoud Rajavi created the National Council of Resistance of Iran.
He was expelled from France in 1986 under a policy of rapprochement with Iran.
The Mojahedin then set up in Iraq at the height of the war with Iran, fighting alongside Saddam Hussein's troops, which led to them being declared "traitors" by Tehran.
The Council in France has been led since 1989 by Rajavi's wife Maryam Rajavi.
The organisation has often been compared by detractors to a sect, with the leading couple its gurus. Maryam Rajavi was officially named the Council's leader in 1993.
Its fighters claimed several operations in Iran, including against oil installations in 1993, and they were blamed for dozens of murders.
- Driven from Iraq -
In Iraq, after Saddam was toppled in 2003 the Mojahedin were officially disarmed and regrouped in the Ashraf camp to the northeast of Baghdad.
It became the PMOI's biggest base in exile housing up to 3,500 people.
In February 2012 they accepted to leave the camp to settle near to Baghdad before leaving Iraq for Albania at the request of the US and UN in May 2013.
In 2003 Maryam Rajavi was among 160 people arrested and then freed in France after two weeks of protests by her supporters, marked by two people setting themselves on fire.
A vast judicial probe into suspected terrorist activities was ended without charges in September 2014.
The European Union in January 2009 struck the Mojahedin from its list of terrorist organisations, where it had been since May 2002. The United States did the same in September 2012.
It is unclear how much support the group continues to have inside Iran.