Special to WorldTribune.com

NICOSIA — Islamic State of Iraq and Levant has been engaged in its biggest campaign in Lebanon.

Lebanese sources said ISIL deployed 500 fighters in its campaign to seize northern Lebanon. They said ISIL deployed mortars, rocket-propelled grenades and machine guns in a four-day battle with the Lebanese Army backed by Hizbullah around the northern city of Tripoli.

“ISIL took heavy losses but most of the fighters managed to flee [Tripoli],” a source said.

On Nov. 2, ISIL and its allies overran U.S.-backed rebels throughout northern Syria. Al Qaida-aligned militias captured bases of rebels trained and equipped by the CIA as well as a large arsenal of U.S. weapons in the Idlib province.

The sources said the Lebanese Army operation consisted of more than 2,000 soldiers as well as an undetermined number of Hizbullah troops. They said about half of the ISIL force was either captured or killed. Later, Hizbullah battled the Nusra Front for the Defense of the Levant in Syria’s Qalamoun mountains along the Lebanese border.

Over the last three months, ISIL was said to have made significant inroads in Lebanon. The sources said ISIL worked with Nusra along the Bekaa Valley as well as the Sunni north near the Syrian border.

The sources said ISIL pressed Sunni soldiers to leave their army units. But only a handful of Sunnis were said to have defected.

“All calls to defect from the army and incite the Sunni youth, in particular to leave their posts and join armed organizations in Lebanon or abroad, are condemned and rejected,” former Lebanese Prime Minister Saad Hariri said.

The sources said ISIL was still in Tripoli. They said nearly 100 fighters were hiding in either the city or the neighboring Palestinian refugee camp and waiting for the army to leave.

“ISIL has the money and weapons to organize another force within a month,” the source said.

  fights Hizbullah in N. Lebanon, ISIL overruns U.S.-backed rebels, WorldTribune.com