The Lebanese army helicopters targeted on Tuesday the posts of the Islamic State fighters on the outskirts of Ras Baalbek, while army units heavily deployed in the al-Qaa region until the outskirts of Ras Baalbek.
Earlier, Hezbollah repelled an attack by the Islamic State on the outskirts of the Bekaa region of al-Qaa and Ras Baalbek near Syria's border.
The party's media outlet al-Manar TV reported that fighters from Hezbollah thwarted an attack by jihadists at dawn on the al-Mazbaha hilltop between Jouseih and al-Qaa.
Hezbollah fighters inflicted several casualties in the ranks of the Islamist group, destroying around 5 vehicles.
On Sunday, Hezbollah fighters continued their advance in the mountainous regions of Arsal where they took control over the hills of Qorney al-Tannour, leaving several al-Nusra Front fighters killed, the Hezbollah-run al-Manar TV channel reported.
Similarly, the Syrian army, backed by Hezbollah, took control over al-Hamra – al-Qusair crossing, which links the mountainous region of Flita with Arsal and is considered of major importance for al-Nusra Front.
Last week, the Lebanese group said in a statement its fighters had seized three hilltops in the mountainous area east of the Lebanese town of Arsal, the target of an incursion last August by the al Qaeda-linked Nusra Front and Islamic State.
Hezbollah's support has been crucial to Syria's President Bashar al-Assad in the four-year-long Syrian conflict.
Its operation in the Qalamoun mountains north of Damascus is part of Assad's effort to shore up his control over western Syria.
Assad has lost swathes of northwestern and eastern Syria in the last two months to an array of insurgent groups including both the Nusra Front and Islamic State, putting him under the toughest military pressure he has faced since the war began.