Lebanese army artillery has been pounding areas around Arsal on the Syrian border for three days in a bid to expel Islamists who invaded Lebanese territory in force for the first time since the Syrian war erupted. Lebanese officials described the incursion by al Qaeda offshoot Islamic State as a planned attack, after its push into Iraq and Syria. Thirteen Lebanese soldiers have been killed in the fighting and at east two dozen have either been taken hostage or are missing. The Lebanese army said it had taken full control of a school seized by the Islamists and found 50 bodies there.