Lebanon Tripoli Jihadi battle
Lebanese army soldiers carry their weapons during clashes with Islamist militants in Tripoli October 25, 2014REUTERS/Stringer

Lebanon's Military Court has indicted 17 Lebanese nationals for belonging to the Islamic State (Isis).

Lebanese authorities are facing an explosive front line, where Lebanese soldiers and Shiite Hezbollah guerrillas are being progressively pulled into deadly fighting with Sunni militants along the country's border with Syria.

As the country steps up its battle against IS, the Lebanese authorities charged 17 suspects with belonging to a terrorist group and engaging in the latest round of clashes in the northern Lebanese city of Tripoli. They were also indicted on the grounds of committing the murder and attempted murder of Lebanese troops, and attempting to travel to Syria to fight alongside IS.

Last month, IS called on Syrian militants to expand into Lebanon to serve as a geographical extension of the Islamic State.

Tripoli battle

Six of the indicted suspects are in custody while 11 were indicted in absentia, judicial sources said.

The suspects were all involved in clashes between the Lebanese army and jihadi militants, thought to be linked to Islamic State and al-Qaeda. The fighting shook Tripoli in October last year.

The Sunni militants threatened to kill soldiers they had captured, unless the army halted its operations.

At the time, al-Nusra Front, al-Qaeda's Syrian affiliate, said in a statement: "We call on it to lift its siege and accept a peaceful solution, or else we will be forced in the coming hours to bring closure to the issue of the soldiers we are holding hostage, given that they are prisoners of war."

After the clashes, the army arrested several suspects including six of the suspects currently in custody, who were arrested while attempting to flee to Syria, via Turkey, from Tripoli's port.

A growing number of Lebanese nationals have joined the militant group, amid recent cross-border attacks and the beheading of Lebanese soldiers by IS fighters.