The army is on high alert along the northern border out of concern that Hizbullah will fire rockets - or use Palestinian proxies to do so - in response to the IDF's escalation of its operations in Gaza. This would open a second front for Israel as it operates against Hamas in the South. On Saturday, Saeed Jalili, the secretary of Iran's Supreme National Security Council, arrived in Syria to discuss the situation in the Gaza Strip. According to media reports, Jalili said Iran and Hizbullah had reached an agreement under which the Lebanese group would launch rockets into Israel if the IDF began a ground operation in Gaza. Two weeks ago, the Lebanese army discovered eight Katyushas ready to fire north of the southern Lebanese town of Nakoura. Defense officials said at the time that it was likely that Palestinian groups - which were behind two rocket attacks last year against Kiryat Shmona and Shlomi - were planning to fire the rockets to demonstrate their allegiance to Hamas. "We will not tolerate an attack in the North," a senior defense official said. "The IDF is versatile and flexible, and if the need arises, it knows how to move forces and fight on a number of fronts." We hope the northern border will remain quiet," Defense Minister Ehud Barak said on Saturday evening. "But we are ready for any development." The Second Lebanon War was spurred by the supposed capture of IDF reservists Ehud Goldwasser and Eldad Regev in a cross-border raid on the North, two weeks after the IDF invaded Gaza following the abduction of IDF tank gunner Gilad Schalit by Hamas near Kerem Shalom on June 25, 2006. Another element that has Israel concerned is that the first anniversary of the assassination of Imad Mughniyeh - the Hizbullah military commander who was killed in a Damascus car bombing in February - is approaching and that the group is seeking revenge. The fear is that Hizbullah will take advantage of Israel's preoccupation in Gaza to carry out a retaliatory attack.