BEIRUT — When Shadi Mawlawi and Osama Mansour escaped their native city of Tripoli in November during clashes between the Lebanese army and the local, armed militant groups they led, they found refuge among Salafist factions inside the Ain al-Hilweh Palestinian refugee camp in Sidon. Lebanese troops have only rarely ventured into the Palestinian camps, despite the 1987 abrogation of the 1969 Cairo Agreement between the Palestinian leadership and the Lebanese government that the army refrain from entering them. Mawlawi and Mansour, the most wanted men in Lebanon, have been charged in absentia with belonging to an armed terrorist group with the intent to carry out attacks. Amid recent rumors that the Islamic State (IS) is planning to declare an emirate in Lebanon, many fear the group might make an appeal to some of the Palestinian factions there to join forces.

Palestinian individuals have been identified among the perpetrators involved in a series of car bombs and suicide attacks targeting Lebanese army and Hezbollah strongholds in the past few years. In one incident in February 2014, Nidal al-Mghayer, a Sidon resident with relatives in Ain al-Hilweh, was identified as the driver of a car bomb that exploded outside the Iranian Cultural Center in Beirut. Those carrying out the attacks do not like that the Iranian-backed Shiite Hezbollah is fighting alongside the Syrian army against predominantly Sunni rebels in the ongoing civil war in Syria, and they complain that the operations conducted by the Lebanese army only target Sunni groups.

New measures implemented by the Lebanese military over the last year have improved the security situation in the country, but tensions remain. “The fear is that IS and other regional groups, such as Jabhat al-Nusra, that threaten Lebanon's stability could find support in the camps,” said an army official who requested anonymity. Naim Abbas, one of the IS leaders killed last August during clashes with the Lebanese army in the northeastern town of Arsal, was a Palestinian from the Burj el-Barajneh refugee camp in Beirut. Abbas, born in Ain al-Hilweh, was allegedly a key figure behind the series of suicide attacks and car bombs that rocked the capital from mid-2013 to the summer of 2014.

Last summer, after lengthy negotiations between the Palestinian factions and Lebanese authorities, a 150-member joint Palestinian patrol was deployed inside Ain al-Hilweh with the purpose of tamping down outbursts of deadly, factional violence, primarily between Fatah and Salafist groups. The number of incidents plunged after July 8, the day of the joint patrol's deployment covering most parts of the camp. Only two incidents have since been reported, whereas the previous year, the camp experienced a series of security incidents that left dozens of dead and wounded. The patrol consists of fighters from Fatah, Hamas and the Popular Front for the Liberation of Palestine (PFLP), while the Salafist Fatah al-Islam, Jund al-Sham and Asbat al-Ansar declined to join.