During the Imposed War (Iran-Iraq War), the fifth column cooperated with the Ba' athist regime of Iraq through actions such as revealing the timing of operations and the deployment locations of Iranian forces, assassination attempts against combatants, sabotage operations, and defection.

The use of the term ‘ fifth column’ in military literature began when General Franco used it in reference to his supporting forces in the city of Madrid, telling reporters in the final stage of the Spanish Civil War: ‘ My forces are advancing on the capital in four columns from four directions, but a fifth column will also join them from within the city and will crush the enemy. ’ Since then, the term ‘ fifth column’ has referred to forces that, from behind the front lines or from within a government, act in concert with the enemy to strike against it and pave the way for its defeat.⁠[1]

Before the victory of the Islamic Revolution, there were instances of the fifth column playing a role in favor of foreign forces. For example, in the Jangal Movement, individuals who had infiltrated the inner circle around Mirza Kuchak Khan Jangali dealt blows to Mirza' s movement and ultimately brought about his martyrdom.⁠[2]

With the victory of the Islamic Revolution as well, the fifth column took action in order to strike at the Islamic Republic. After the seizure of the American spy den in Tehran by students following the Imam' s line, documents were published showing that certain cultural and political figures — such as Shahram Homayoun (managing director of the Bamdad newspaper), Fariborz Attarpour (one of the editors of the Tehran Journal), Alireza Farahmand (head of the foreign desk of the Kayhan newspaper), Massoud Mohajer (one of the editorial officials of the Ayandegan newspaper), Rahmatollah Moghaddam Maraghei (governor of East Azerbaijan in the provisional government and member of the Assembly of Experts for the Constitution), and Hassan Nazih (head of the Bar Association and the first head of the National Iranian Oil Company in the provisional government) — were working to preserve American interests in the country.⁠[3] Seyyed Mohammad-Reza Sa' adati, one of the senior members of the Mojahedin-e Khalq Organization, also spied for the Soviet Union in the role of a fifth column after the victory of the Islamic Revolution; he was arrested on 6‌^th   Ordibehesht 1358 [26 April 1979] while meeting with a Soviet embassy officer in Tehran, carrying a briefcase containing documents and records.⁠[4]

The ‘ Arab People' s Political Organization’ was also among the groups that, on the eve of the Imposed War, served as a fifth column for the Ba' athist regime of Iraq, attempting to partition Khuzestan province by creating unrest and insecurity there.⁠[5] During the Imposed War, individuals from various political groups cooperated with Saddam through military, security, and political sabotage actions.

The fifth column' s activities during the Imposed War took place in two areas: the ‘ war zones’ and the ‘ home front. ’

In the operational areas, fifth-column forces infiltrated the defenders of the city of Abadan and disclosed their deployment locations,⁠[6] and by providing sensitive military information to the enemy, inflicted many blows. The fifth column, by leaking the operations of the Martyrs Rajaei and Bahonar (11‌^th   Shahrivar 1360 [2 September 1981]),⁠[7] the Preliminary Val-Fajr (17‌^th   Bahman 1361 [6‌^th   February 1983]),⁠[8] and Karbala 4 (3‌^d Dey 1365 [24 December 1986]),⁠[9] caused the martyrdom, wounding, and capture of more than 20,842 members of Iran' s armed forces.⁠[10]

Before the Martyrs Rajaei and Bahonar operation, Vahid Hajiloo, an infiltrator of the Mojahedin-e Khalq Organization (Monafeqin) within the public relations office of the Hamedan IRGC — who had taken part in every stage of the operation' s reconnaissance — went to Tehran under the pretext of printing propaganda materials for the combatants, and sent information related to the operation to Iraq through his contact in the Mojahedin-e Khalq Organization. After being identified by the Islamic Revolutionary Guard Corps, Hajiloo was executed by order of the Tehran Revolutionary Court.⁠[11]

The trace of the Mojahedin-e Khalq Organization' s fifth column can also be seen in the failure of the Preliminary Val-Fajr operation. Mohsen Sarb-Ahrabi, a member of this organization, had infiltrated the operations intelligence unit of the 27th Mohammad Rasulallah (PBUH) Brigade of the Revolutionary Guards and took part in the reconnaissance of the Preliminary Val-Fajr operational area; he disappeared at the same time as the operation. Sometime later, Ahrabi, in an interview with Iraqi radio, spoke about his role in exposing this operation. After the end of the Imposed War, he returned to the country along with Iranian prisoners of war, and after being identified and tried, he was executed.⁠[12]

In addition to the Monafeqin, the clandestine military branch of the Tudeh Party known as ‘ Nowid, ’ composed of individuals such as Colonel Houshang Attarian (commander of the Nezaja' s Western Advance Headquarters) and Navy Captain Bahram Afzali (commander of the Army Navy), also played a role in disclosing information related to the Preliminary Val-Fajr operation; they were executed after being tried in the Revolutionary Court.⁠[13]

Assassination attempts against Iranian forces in the operational areas and on the home front were among the other actions of the enemy' s fifth column. For example, one of the IRGC forces discovered that two anti-vehicle mines had been planted on the Zarrin Abad– Dehloran road; fifth columnists from Dehloran, who had planted these mines, were arrested.⁠[14] In another case, Qassem Soleimani (martyr; commander of the 41st Tharallah Division of the Revolutionary Guards during the Sacred Defense) was the target of an assassination attempt by a physician who was a member of the Monafeqin at Qaem Hospital in Mashhad, but he was saved with the help of a nurse.⁠[15]

The defection of some military personnel along with military equipment was another of the fifth column' s actions during the Imposed War. Captain Ahmad Moradi Talemi (an F-14 fighter pilot) defected in 1364 [1985/86] with his fighter jet, first to Iraq and then to Switzerland. Three months later, he was killed by an unknown assailant.⁠[16] Ali-Akbar Mohammadi (pilot of a non-combat Falcon-20 jet) also, in 1365 [1986/87], flew first to Iraq and then defected to West Germany; five months later, he was killed by two unknown assailants in Hamburg.⁠[17]

The enemy' s fifth column also carried out actions on the home front, such as distributing anti-war leaflets, writing slogans in various places including on streets, setting fire to cars and motorcycles, disabling military equipment, and generally creating disruption within military establishments.

The Mojahedin-e Khalq Organization, in its report on the sabotage actions of its forces, referred to actions such as: disabling the engine of an army air force F-4 aircraft; disabling the engine of a C-130 aircraft; destroying the locks of rooms at the Khorramshahr naval base; destroying the door locks of vehicles belonging to personnel of the Bandar Imam Khomeini naval base; disabling the turbine of a C-130 aircraft; disabling the navigation system of two F-14 (Tomcat) fighter jets at the 8th Tactical Fighter Base in Isfahan; disabling the engines of two F-14 (Tomcat) fighter jets at the Tehran Aircraft Manufacturing Industries organization; disabling a Chieftain tank at the Masjed Soleyman tank manufacturing industry; destroying the main entrance door lock of the army garrison mosque in Masjed Soleyman; destroying the large transport fuel tank of the Tabriz army ground forces garrison; setting fire to two Toyota station wagons belonging to the Islamic Revolutionary Guard Corps in Miandoab; destroying 21 sensitive parts of equipment at the army air force garrison in Tehran, valued at approximately 35,000 dollars; destroying an armored personnel carrier at the army ground forces garrison in Tabriz; disabling the engines of 7 army ground-forces trucks in Khash; and destroying the warehouse door of the Qasr garrison and the Zolfaghar Brigade garrison.⁠[18]

On the political front as well, groups opposed to the Islamic Revolution sought to weaken the Iranian government, among which the actions of the Freedom Movement of Iran in opposing the defense against the Ba' athist aggressors are the most evident.⁠[19]