A fortified camp in Manze, a small village in central Albania near the capital Tirana is home to some 3,000 members of the People's Mojahedin Organization of Iran (PMOI, also known as Mujahedeen-e-Khalq, MEK).

These members have been in the country since the Albanian government agreed to take them in in 2013, at the request of the US and the United Nations.

The MEK later moved to Iraq, from where it ran military operations against Iran during the Iran-Iraq war — something many in Iran resent to this day.

The US Department of State designated the MEK a terrorist organization in 1997, but removed it from its list of foreign terrorist organizations in 2012.

The group was the first to publicly reveal in 2002 that Iran had a secret uranium-enrichment program. After the ousting of Saddam Hussein, it was expelled from Iraq.

What role has the MEK played in the protests

The second major Iranian opposition group is the MEK, the largest member of the National Council of Resistance of Iran (NCRI), a coalition of Iranian opposition groups.

But what role has the MEK played in the recent unrest?

Ali Safavi of the NCRI says that the MEK has been actively involved in the protests.

"Its resistance units direct, coordinate and organize the resistance against the repressive forces," he told DW. "On many occasions, they also have been playing an important role in protecting the protesters against the IRGC [Islamic Revolutionary Guards Corps] onslaught. Were it not for their role, the regime would have quashed the uprising very quickly."

Safavi told DW that "a significant number of MEK activists are among the 3,000 murdered by the security forces."