The People's Mujahedeen, or Mujaheddin-e-Khalk, or MEK, was founded in 1965 by Massoud Rajavi, as a militant opposition group fighting the Shah and organised around a strict Marxist-Leninist hierarchy.
Initially the group aimed to link up with Ayatollah Khomeini, but the religious leader banned them instead after he successfully overthrew the regime of the Shah in 1979.
The MEK reacted with a massive, nationwide bombing campaign, which Tehran answered with waves of arrests and executions.
The group then found refuge in Iraq where they were trained by troops of Saddam Hussein who put tanks and military equipment at their disposal.
After Saddam’s demise, they eventually moved to a camp in Albania, funded by $20 million (€17 million) from the US meant to used to “de-radicalise” the groups’ 3,000 members.
MEK In France
Meanwhile, the political wing of the MEK, the National Council of Resistance of Iran (NCRI) found shelter in Auvers-sur-Oise, a small town outside Paris, where they reside in a walled compound in an uneasy relationship with the French government.
The groups current leader is Maryam Rajavi, wife of the group's founder Massoud Rajavi who dissapeared in 2003. It is not known if he is still alive.
In 2010 a court in Iraq accused him and 39 others, including Maryam, of “crimes against humanity,” encompassing involvement “with the former Iraqi security forces in suppressing the 1991 (Shi’ite) uprising against the former Iraqi regime and the killing of Iraqi citizens," according to Judge Mohammed Abdul-Sahib, then a spokesperson for the Iraqi High Tribunal, who was quoted by Reuters.
The group also targeted Americans and was on the State Department’s list of terrorist organisations from 1997 and on the EU terrorist list.
But things had already started to change in 2002, when the MEK revealed Iran’s nuclear program.
The revelations, based on satellite pictures, triggered a massive international response resulting in calls for sanctions that were eventually imposed.
During years of intensive lobbying, following the nuclear revelations, the group managed to get itself off EU (2009) and US (2012) terrorist lists, presenting themselves as a democratic alternative to the current regime in Iran.
They also won the support of many influential politicians.
The foreign guest list of the MEK’s yearly gatherings is impressive.
Present at this year's meeting in Villepinte were former New York mayor Rudy Giuliani, former US Speaker of the House Newt Gingrich, former French minister of Foreign Affairs Bernard Kouchner, MEPs and MPs from various European countries, human rights activists and journalists.
“Speakers, they get paid for speaking,” says Massoud Khodabandeh, a former member of the MEK, who managed to get out of the organisation and lives now in the UK, where he heads Middle East Strategy Consultants.
Khodabandeh, who says he worked for the MEK’s security department, describes the group as a “destructive cult,” where members are forced to divorce, sex is not allowed, access to health services is “limited” and members are obliged to work for free “in a modern version of slavery.”
“Disobedience of the leaders is met with harsh punishment,” he says.
He claims much of the money to pay for the group's overheads and massive public relations exercises comes from Saudi Arabia.
“Personally, in the 1980s, I went to Riyadh and I brought three lorries full of gold for the Mujaheddin. In those years, the relationship between the Saudis and the Mujaheddin was clandestine, they wouldn’t say it.
The relationship is not secret anymore, given the fact that Saudi Prince Turki-al-Faisal himself came to the yearly MEK gathering in 2016.
Meanwhile, the big names add to the legitimacy of the group.
“I know that in their history there are controversial moments and critical moments,” says Marcin Swiecicki, a Polish Member of Parliament who travelled to Paris to attend the MEK meeting.
“But I understand that they have evolved over time and they are accepted by the democratic leaders of Europe, including Kouchner, the former Prime Minister of Canada, [Stephen] Harper, so somehow I trust these people who are supporting them and that is why I joined them.”
One of the political heavyweights who support the MEK, US National Security Advisor John Bolton, singled the group out to take over the government in Iran after a possible “regime change.”
But their lack of popularity inside Iran may play against them.
“One of my neighbours was killed by these people,” says Mohammad Marandi, a scholar with Tehran University who remembers the MEK bombings from the time he was a teenager.
“They exploded a bomb very close to my old house where we used to live as I was getting ready to go to school at 8am, and all the windows in our house were broken and of the neighbours’ houses and a family of a father, a mother and two children, they were killed," he said.
“So we have very bad memories of this group that was supported by Saddam Hussein and that exploded bombs across Iran and assassinated people,” he says.
As for the alleged bomb plot against the MEK itself at its “Free Iran 2018” meeting in Villepinte last Friday, that was attended by some 25,000 people and that took place just days before Iran’s president Hassan Rouhani was to visit Europe. Investigations are still ongoing.
Israel and the MEK itself are accusing Iran. According to the MEK’s website, a “terrorist diplomat of the clerical regime by the name of Asdollah Assadi,” who is allegedly the “station chief of the Ministry of Intelligence and Security (MOIS) in Vienna” since 2014, is the mastermind behind the alleged attack.
In its turn, Iran says that the plotters were the MEK’s own members, instructed to carry out the attack so Iran would get the blame.
And Iran's Foreign Minster Javad Zarif, commented in a tweet about the timing of the incident, adding that Iran “unequivocally condemns all violence and terror anywhere, and is ready to work with all concerned to uncover what is a sinister false flag ploy."
But once again, the controversial fringe group finds itself in the focus of international attention.