BEIRUT: The Lebanese Army came under rocket attack by Daesh (ISIS) in northeast Lebanon Monday, prompting soldiers to hit back with considerable force, hours after President Michel Aoun called for a Tuesday meeting of the Higher National Defense Council.

Security sources confirmed to The Daily Star that four Grad rockets were launched by militants at Army outposts in Al-Qaa. Four other rockets hit the town’s outskirts and surrounding areas, according to a statement from the Army, which added that the military fired back salvoes of rockets and artillery shells.

A U.S. Air Force C-5 aircraft was spotted landing Monday in the Bekaa Valley’s Riyaq Airport, MTV reported. The U.S. conducts routine flights to the eastern airport, but the timing of this flight suggests that the plane may have been delivering logistical support to the Army for the upcoming operation.

One week has passed since the Army warned of a looming offensive to crush the presence of Daesh extremists in Lebanon and push them outside of the country’s borders.

The Army kept up its daily shelling of Daesh positions throughout the day Monday and into the evening. No injuries were reported from the LebaneseArmy, but Daesh suffered multiple casualties, military sources said.

Although an all-out offensive has not reached zero hour, President Aoun called for a Higher National Defense Council meeting to be held at Baabda Palace Tuesday. The meeting will be headed by the president and will focus on military plans to launch an offensive against Daesh on the outskirts of Al-Qaa and Ras Baalbeck and the current security situation in the country.

A source told The Daily Star that the offensive against Daesh is not expected to start before Wednesday. This suggested start date indicates that the door has not yet been shut on negotiations with Daesh. Authorities have attempted to conduct indirect talks to gain concrete information on the fate of nine servicemen held by the group, in return for the militants’ guaranteed withdrawal to Daesh-held territories inside Syria.

The servicemen are still missing after being kidnapped by Daesh in 2014, after extremists overran Arsal, in Lebanon’s northeast.

Foreign Minister Gebran Bassil said Monday that Lebanon was approaching a time that would require sacrifices. Addressing families living in Al-Qaa, Bassil said, “We are approaching a time that will see blood and martyrs.” Meanwhile, Interior Minister Nouhad Machnouk said preparations by the Army were ongoing ahead of the highly anticipated battles. “The Army’s preparations are moving forward as necessary ... and Army Commander Gen. Joseph Aoun is a courageous and responsible man,” Machnouk told reporters following a meeting with Grand Mufti Sheikh Abdel-Latif Derian.

Responding to questions about the potential participation of Hezbollah in the forthcoming battles, Machnouk dismissed this as an option. “The words of the defense minister are clear,” he said, “and this possibility is out of the question.”

Sunday, Defense Minister Yaacoub Sarraf said the Army did not and would not need the assistance of anyone in its battle against Daesh.

Machnouk met Monday with U.S. Ambassador to Lebanon Elizabeth Richard and new U.S. Deputy Chief of Mission Ed White. During the meeting, Richard reaffirmed the U.S.’ ongoing support for the Lebanese Army.

The Army receives around $80 million in U.S. training, equipment and funding a year – nearly $1 billion in the last 10 years.

It is anticipated that zero hour for the next offensive will not arrive until the removal of Syrian rebels from a previous battle between Hezbollah and Jabhat Fatah al-Sham – formerly known as the Nusra Front – is completed.

Around 3,000 Syrian refugees, including rebels belonging to a Free Syrian Army-affiliated rebel group will be leaving Lebanon this week, sources said Monday. Sources close to Saraya Ahl al-Sham told The Daily Star that the refugees as well as around 400 rebels were ready to leave the northeastern town of Arsal to eastern Qalamoun.

“The total up until now is 3,000 including military personnel and civilians, and the destination is to liberated eastern Qalamoun,” the source said. “The move will take place this week but the timing isn’t set yet. There has been coordination between the Lebanese state, the Syrian state and Hezbollah.”

The source said that there were certain obstacles that had prevented this movement from previously taking place.

Last week, some 8,000 Syrians, including hundreds of Jabhat Fatah al-Sham militants, were transported to Idlib in Syria after Hezbollah seized positions the militants had previously held on both sides of the Lebanese-Syrian border, east of Arsal.