Upon arriving in Southern Lebanon, the locals sympathized with their catastrophic conditions, and many were sheltered in Abdul Husayn Sharaf ad-Dine's al-Ja'fariyya school until the authorities dealt with the situation.
[3][4] Even before the establishment of the Palestine Liberation Organization (PLO) in 1964, exiled Palestinian intellectuals residing in Lebanon and other Arab countries began to form clandestine paramilitary groups in the late 1950s.
In 1956, Sharaf ad-Dine's al-Ja'fariyya school organized a guerrilla group consisting of 25 Lebanese and Palestinian students with the sole purpose of launching strikes in Israel.
Meanwhile, with permission from Syria, Iran sent a contingent of Revolutionary Guards to Lebanon, tasked with amalgamating, reorganizing and building up the small Shiite religious factions into a new organization - Hezbollah.
Initially, the Syrian government encouraged its favoured Palestinian groups to compete for influence, facilitating the entrance of as-Sa'iqa, PFLP-GC, and the pro-Syrian dissident Fatah faction under Colonel Said al-Muragha (Abu Musa).
This time, Assad recruited the more powerful Shia Amal Movement militia headed by Nabih Berri to dislodge Arafat's loyalists.
By mid-1985 Amal was also in conflict with the Druze Progressive Socialist Party (PSP) and its militia, the People's Liberation Army (PLA), led by Walid Jumblatt in the mountainous Chouf region.
Unlike the majority of other Lebanese leftist militias, the Communist Action Organization in Lebanon (OCAL), led by Muhsin Ibrahim, refused to cooperate with Syria in its attempts to vanquish Arafat.
Allied with the pro-Arafat Palestinian refugee camp militias were the Lebanese Al-Mourabitoun, Sixth of February Movement, Communist Action Organization in Lebanon (OCAL), Druze Progressive Socialist Party (PSP) and Kurdish Democratic Party – Lebanon (KDP-L), who faced a powerful coalition of Lebanese Communist Party (LCP), and Shia Muslim Amal movement militia forces backed by Syria,[5] the Lebanese Army, and the anti-Arafat Fatah al-Intifada, As-Sa'iqa, Palestine Liberation Army, and Popular Front for the Liberation of Palestine – General Command (PFLP–GC) dissident Palestinian guerrilla factions.
Despite prodding from Syria, these political parties and their respective militias contributed nothing more than verbally expressing support for Amal and demanding that Arafat step down.
This left Amal to do the work of dislodging the Arafat loyalists, with some help from Syria's anti-Arafat Palestinian allies, such as As-Sa'iqa, PFLP-GC and Fatah al-Intifada.
Bolstered by newly received heavy weaponry (including Soviet-made artillery pieces[11] and T-55A tanks[12] loaned by Syria), Amal tightened its siege on the camps.
Meanwhile, throughout West Beirut, Amal continued to suppress the remaining predominately Sunni, pro-Palestinian militias such as the small Nasserite Sixth of February Movement in June 1986.
The PLO was also aided by Lebanese-Kurdish fighters from the Kurdish Democratic Party – Lebanon (KDP–L), who lived with their families alongside the Palestinians in the refugee camps.
The situation began to cool on 24 June 1986, when the Syrians deployed some of their Commando troops, assisted by a special task-force of 800 Lebanese Army soldiers and Gendarmes from the Internal Security Forces.
[13] The tension due to this conflict was also present in the South, where the presence of Palestinian guerrillas in the predominantly Shia areas led to frequent clashes.
The third and deadliest battle began on 29 September 1986, when fighting broke out around the Rashidieh camp in Tyre between Amal and locally based PLO groups.
[18] A cease-fire was negotiated between Amal and pro-Syrian Palestinian groups on 15 December 1986, but it was rejected by Arafat's Fatah, who tried to appease the situation by giving some of its positions to the Al-Mourabitoun militia in exchange for supplies to the camps.
[19] Dr Pauline Cutting, a British doctor in Bourj el-Barajneh, was amongst those who gave graphic descriptions, via radio telephone, of conditions in the camps.
The conflict was started when a PSP/PLA fighter, acting on orders from their leader Walid Jumblatt, walked to the Channel 7 TV station (French: Télé Liban – Canal 7) building in the Tallet el-Khayat sector at Msaytbeh and replaced the Lebanese national flag hoisted there by the Druze five-coloured flag,[22] which was interpreted by Amal militiamen as a deliberate act of provocation.
On 21–22 February, the week of fighting was ended by the arrival in West Beirut of 7,000 Syrian Commando troops under the command of Major general Ghazi Kanaan, assisted by Lebanese Internal Security Forces (ISF) gendarmes, who immediately closed over fifty militia "offices" and banned the carrying of weapons in public, detaining in the process many young men with beards suspected of being militiamen and began executing anyone found with unauthorised weapons.
[24] An incident on 24 February in which over twenty Hizbollah supporters were killed led to intense pressure on Syria from Iran and an end to the army’s advance into the Southern suburbs, Dahieh, with its 800,000 Shia residents.
At the end of the war, an official Lebanese government report stated that the total number of casualties for these battles was put at 3,781 dead and 6,787 injured in the fighting between Amal and the Palestinians.
The real number is probably higher because thousands of Palestinians were not registered in Lebanon and the blockade meant that no officials could access the camps, so that all the casualties could not be counted.