The Lebanese army launched an offensive on Saturday against a Daesh enclave on the northeast border with Syria as the Lebanese Shia group Hezbollah announced an assault on the militants from the Syrian side of the frontier.
The Lebanese army operation got underway at 5 am (0200 GMT), targeting Daesh positions near the town of Ras Baalbek with rockets, artillery and helicopters, a Lebanese security source said. The area is the last part of the Lebanese-Syrian frontier under insurgent control.
The operation by Hezbollah and the Syrian army targeted the area across the border in the western Qalamoun region of Syria.
A Hezbollah statement said the group was meeting its pledge to "remove the terrorist threat at the borders of the nation" and was fighting "side by side" with the Syrian army.
It made no mention of the Lebanese army operation.
The army said it was not coordinating the assault with Hezbollah or the Syrian army.
Any joint operation between the Lebanese army on the one hand, and Hezbollah and the Syrian army on the other would be politically sensitive in Lebanon and could jeopardise the sizeable US military aid the country receives.
Washington classifies the Iran-backed Hezbollah as a terrorist group.
"There is no coordination, not with Hezbollah or the Syrian army," General Ali Kanso said in a televised news conference, adding that the army had started to tighten a siege of Daesh in the area two weeks ago.
Characterising the 600 Daesh fighters in the area as 600 "suicide bombers", he added:
It's the most difficult battle so far waged by the Lebanese army against terrorist groups – the nature of the terrain and the enemy
In a recent speech, Hezbollah leader Sayyed Hassan Nasrallah said the Lebanese army would attack Daesh from its side of the border, while Hezbollah and the Syrian army would simultaneously assault from the other side.
A commander in the military alliance fighting in support of President Bashar al-Assad said that "naturally" there was coordination between the operations.
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