Updated

Thousands of people gathered north of Paris on Saturday to support Iranian opposition protesters and an Iranian exile group pushing to be rid of a terrorist label.

Crowds spilled out of buses and filled the fairground in Villepinte under drizzly skies. Organizers said 1,000 buses were hired to bring protesters from around France and Europe, including legislators from several countries.

The rally was organized by the National Council of Resistance of Iran.

The France-based umbrella group includes the People's Mujahedeen Organization of Iran, which was recently removed from the European Union's list of banned terrorist groups. The group, also known as the Mujahedeen-e-Khalq is trying to persuade the U.S. to stop classifying it as a terrorist group, as well.

The leader of the National Council, Maryam Rajavi, is expected to speak later Saturday.

The group organizes rallies in France every year. This year, the standoff over Iran's presidential election results has drawn new attention to groups opposed to the cleric-led Iranian government.

The demonstrators in France are expressing solidarity with Iranian opposition leader Mir Hossein Mousavi's supporters, who have protested in Tehran for several days to demand a new presidential election. Iran's rulers are facing their greatest internal challenge since the 1979 Islamic Revolution.

The People's Mujahedeen Organization of Iran participated in Iran's Islamic Revolution. But it soon fell out with the clerics in charge of the country, and launched a campaign of assassinations and bombings in an attempt to topple the government.

The group's supporters argue it no longer engages in armed struggle, and they have won several court cases in Europe in recent years.

The group is also seeking international support for some of its fighters, who are confined in a U.S.-run camp north of Baghdad called Ashraf City. Iraq's government has called for the members of the group — which was allied with Saddam Hussein before his ouster from power in 2003 — to be deported.

At Saturday's rally, many protesters wore yellow vests reading "Viva Ashraf" or "Our Choice: Maryam Rajavi."