For two years before the official outbreak of the Iran-Iraq War on September 22, 1980, Iraq carried out repeated border violations against Iran. Following the victory of the Islamic Revolution, Iraqi border activities began in the form of arms smuggling into Iran, illegal crossings by affiliated agents, engineering operations, and border bombardments.⁠[1] Iran’s first response dates back to early 1979. The first Iraqi border violation occurred on April 2, 1979, when an Iraqi helicopter flew over Mehran city and the Bahramabad border post. Iran subsequently lodged a formal protest with Iraq.⁠[2]

From early 1980, Iraqi aircraft, helicopters, and tanks were conducting daily patrols and operations near the border, repeatedly violating Iranian territory.⁠[3]

Beginning in the spring of 1980, the Iraqi government insisted that Iranian vessels passing through the Arvand Rud install the Iraqi flag on their decks; otherwise, ships flying the Iranian flag were subjected to harassment.⁠[4] During the summer of 1980, Iraq intensified its military movements and carried out several military operations every day along Iran’s border.⁠[5]

Between September 2 and 4, 1980, border clashes broke out near Qasr-e Shirin. Iran announced that Iraq was seeking a pretext for launching an attack.⁠[6] Iraq, in turn, accused Iran of artillery attacks on Iraqi border towns, including Mandali, Zurbatiyah, and Naftkhaneh.⁠[7] On September 6, 1980, Iraq claimed that, in response to the border clashes, it would occupy 350 square kilometers of Iranian territory from Qasr-e Shirin to Musian—areas that, under the 1975 Algiers Agreement, should have been handed over to it.⁠[8] According to this agreement, Iran was supposed to relinquish ownership of these areas in exchange for access to half of the Arvand Rud.⁠[9]

From September 7 to 11, 1980, the Iraqi army launched serious attacks in western Iran and occupied parts of Iran’s border regions, including the Meimak, Khan-Leili, and Zayn al-Kash heights near Qasr-e Shirin. With the occupation of the Zayn al-Kash on September 7, the main border road from Qasr-e Shirin to Naft-Shahr and Soumar—from Tangab-e Kohneh to Soumar—effectively came under Baathist control.⁠[10] On September 8, Iraqi fighter jets bombed Qasr-e Shirin, and the following day, they violated Iranian airspace over Khosravi.⁠[11]

On September 10, 1980, Iraqi radio announced that Iraq’s armed forces had occupied about 80 square kilometers of disputed territory in the Qasr-e Shirin area, including Saif Saad and Zayn al-Qaws⁠[12] (or Zayn al-Kash), south of Qasr-e Shirin and near Naft-Shahr.⁠[13] On September 14, it also reported the occupation of another 140 square kilometers near Musian and Diyaleh, and Haeleh-Khodir villages.⁠[14] Iraq’s main objective was not merely taking control of Iranian territory but facilitating broader military operations for the expansion of the war.⁠[15]

On the 11th of September 1980, several Iraqi tanks crossed into Iranian territory from the Aq-Dagh Heights near Qasr-e Shirin.⁠[16] Two days later, the Talkhab border post north of the Meimak was also occupied by Iraqi troops. In the meantime, Iraqi fighter jets bombed the Khan-Leili area and also later on the Chegar region in Ilam. Moreover, Gerde-Nou and Bishgan in Sarpol-e Zahab, as well as Baba-Hadi villages in Qasr-e Shirin, came under airstrikes on September 15 and 16, respectively.⁠[17]

In response to Iraq’s border violations, Iran filed complaints with international organizations and carried out limited countermeasures,⁠[18] including bombing several military facilities inside Iraq. One such response was an Iranian Army Air Force strike targeting military units in Zurbatiyah, inside Iraq near Mehran, on September 18, 1980. During this operation, an Iranian F-5 aircraft⁠[19] was hit by Iraqi missiles, and First Lieutenant pilot Hussain Lashkari was captured by the Baathist regime.⁠[20]

On September 17, 1980, Iraq unilaterally annulled the 1975 Algiers Agreement, claiming that Iran had already violated it and asserting that the Shatt al-Arab (Arvand Rud) was entirely an Iraqi river. When Iran rejected Iraq’s demand that Iraqi sailors take control of piloting Iranian ships in the Arvand Rud, heavy fighting broke out along the waterway. During clashes on September 19, Iran lost two F-4 fighter jets.⁠[21]

In addition, before the official start of the Iran-Iraq War on September 22, 1980, armed clashes involving anti-revolutionary groups supported by Iraq were underway in West Azerbaijan and Kurdistan provinces. These conflicts tied down a significant portion of Iran’s armed forces.⁠[22]

Iraq’s border attacks prior to the full-scale invasion may have served as a rehearsal to prepare its army for war against Iran. At the same time, it is likely that the Baathist regime pursued another objective: provoking Iran into initiating the war.⁠[23]

Up to September 22, 1980, Iran’s Ministry of Foreign Affairs sent 53 formal protest notes to the Iraqi government.⁠[24] Of the 637 Iraqi border violations recorded before the official outbreak of the war, 130 were aerial, 17 maritime, and 490 were ground incursions.⁠[25] Iran reported a total of 480 ground violations and 150 airspace violations by the Baathist regime to the United Nations before the war officially began.⁠[26] Eighty-four of these violations occurred in 1979, with the remainder taking place up to late 1981. Most border clashes in western Iran took place along the borders of Kermanshah and Ilam provinces, with Qasr-e Shirin as the main focal point, while in the southern border region, violations ranged from Dehloran to the mouth of the Al-Faw.⁠[27] As a result of these pre-war border attacks, 105 Iranians were martyred, 548 were wounded, and 119 were taken prisoner.⁠[28] In addition, 150 square kilometers of Iranian territory were occupied by Iraq before the official outbreak of the war.⁠[29]