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The Fajr Forces, a little-known Sunni armed group operating in south Lebanon, have made a resurgence in recent weeks after almost 20 years of relative inactivity.
Along with other Hezbollah allies, the group has intensified attacks on Israel as the border conflict threatens to draw Lebanon into a full-blown war with its southern neighbour.
Their alliance is a strategic one, said Bassem Hammoud, the deputy head of the political bureau of the Islamic Group, under which the Fajr Forces operate.
“We are not in complete alignment with Hezbollah,” said Mr Hammoud, speaking to The National from his office in the southern city of Saida last week. “We disagree with them on some things. But we are with them in terms of resistance against Israel.”
Most recently the group claimed responsibility for a volley of missiles which struck in the northern Israeli city of Kiryat Shmona on Sunday.
It was the most serious escalation by armed groups in Lebanon since the border conflict erupted on October 8.
No casualties were reported although two buildings caught fire, according to Israeli media.
The Fajr Forces warned that it was able to “expand the scope” of its strikes on Israel if attacks on south Lebanon and Gaza continued.
As Israel escalates its war on the Hamas-controlled Gaza Strip, prompting intense retaliation from ally Hezbollah, many residents fear Lebanon – currently undergoing a severe economic crisis – could become a new front for a broader regional conflict between Israel and Iran-backed groups and their allies.
“We also don’t want a war,” said Mr Hammoud. “We’re in a defensive position. We hope not to meet the enemy, but if we must meet him, we will.”
Hezbollah, which controls Lebanon’s south, has permitted Palestinian groups operating in the country as well as allied Lebanese groups such as the Fajr Forces to launch attacks on Israel.
“Hezbollah controls the southern region, and it has the capabilities to gather intelligence as well as the experience to understand when and from where to attack,” said Mohanad Hage Ali, a senior fellow at the Carnegie Middle East Centre in Beirut.
“This permits the organisation to effectively control who uses the southern front.”
The attack by the Fajr Forces is just one of dozens of incidents happening daily between Israel and armed groups in Lebanon since the outbreak of the Israel-Gaza war.
But the cross-border bombardment has significantly intensified since last week, when Israel announced the “second stage” of its war on Hamas.
“We have seen a widening of the geographic area in which the military operations are happening,” said Mr Ali.
Who are the Fajr Forces?
The Islamic Group – a Lebanese Sunni political party considered to be an offshoot of the Muslim Brotherhood – was founded in 1964. It currently boasts one seat in Lebanon's parliament.
The group’s military wing was established in 1982 as a direct response to the Israeli occupation of south Lebanon. The group has since been considered an ally of Hezbollah.
While the Saudi-brokered Taif agreement that ended Lebanon’s 1975-1990 civil war stipulated the disarmament of the country's many militias, the measure exempted “resistance” groups in the south from surrendering their weapons until a full Israeli withdrawal was completed.
“The Taif agreement legitimises resistance against Israeli occupation, and so does every government’s ministerial statement since the end of the war,” Mr Ali said.
“Al Fajr would fall under this resistance banner. It is an attempt by Hezbollah to diversify resistance in an attempt to ensure wider Sunni support.”
Israel withdrew from Lebanon in 2000, but the Lebanese state does not consider it a full withdrawal and says Israel still occupies slivers of land in Ghajar, the Kfarshouba hills and the Shabaa farms.
The armed group conducted operations against Israel during the month-long 2006 Lebanon war between Israel and Hezbollah, in which much of Lebanon’s vital infrastructure was destroyed.
Little had been heard of it since, until the present border conflict erupted and the group officially announced its involvement last Wednesday.
“Today, with the renewal of Israeli attacks on Lebanon, the deaths of journalists and of civilians in their homes, we rise to confront the enemy. We will continue to take part in the conflict,” Mr Hammoud said.
“We are actively taking part in the southern front. We were, we are, and we will continue to stand up against the Israeli enemy.”
What does the Fajr's involvement mean?
What began as a tit-for-tat border conflict has gradually expanded over the weeks, in direct proportion to the intensity of the war in Gaza.
At first, Hezbollah mostly targeted Israeli military instalments and vehicles. It allowed Palestinian groups such as Islamic Jihad and Hamas to cross into Israel for limited operations, easily repelled by Israel.
But Hezbollah and its allies have escalated attacks on Israel since the latter’s high-intensity bombardment of Gaza on Friday, which was accompanied by a ground operation conducted under the cover of a total communication blackout.
Hezbollah aims to prevent a military invasion of the Gaza Strip, Mr Ali said, or at least keep Israel too occupied to centre its full attention on Gaza.
Israel, in turn, has responded by striking areas up to 20km into Lebanon, no longer limiting itself to the border.
Although not conducted by Hezbollah itself, the Fajr Forces’ rocket attack on Kiryat Shmona served as an unspoken threat by the Iran-backed group that it can further expand the front, even targeting civilian infrastructure, should Israel overstep.