Tens of thousands of Israeli soldiers will stage a mock 10-day war against the Hezbollah terrorist group in northern Israel beginning Tuesday, marking the IDF’s largest exercise in nearly 20 years, the army announced Monday, amid tensions over growing Iranian influence in Syria and Lebanon.

The drill, known as “the Light of the Grain,” or “Or Hadagan” in Hebrew, will start at daybreak Tuesday and end on September 14, the military said. The war games will include naval ships, drones, helicopters and fighter jets taking part.

Tens of thousands of soldiers, including thousands of reservists, will take part in the exercise, which is being run by the IDF’s Northern Corps and its commander Maj. Gen. Tamir Hyman, along with the head of the Northern Command, Maj. Gen. Yoel Strick, and the head of the IDF’s General Staff Corps, Maj. Gen. Yossi Bachar, an army official said, speaking on condition of anonymity.

Get The Times of Israel's Daily Edition by email and never miss our top stories Free Sign Up

The exercise will simulate a conflict with Hezbollah that starts with a sudden, small attack and develops into full-scale war. The official said the military’s goal in the drill will be to “vanquish” the terrorist group.

Hezbollah, with its suspected arsenal of over 100,000 rockets and thousands of fighters, is seen by the IDF as its central threat. The Iran-backed terrorist group is therefore the standard by which the army measures its preparedness.

Israeli officials have raised alarms in recent months over increased Hezbollah activity in southern Lebanon, as well as plans for an Iranian missile factory to supply the terror group with more accurate rockets. They have also expressed misgivings over a ceasefire in southern Syria that they say allows Iran to establish a foothold along Israel’s northern border.

However, the military stressed the exercise was planned in advance and was not connected to Iran’s or Hezbollah’s current activities in the region.

The navy and air force will also take part in the drill, as well as the military’s cyber units, which for the first time in a large-scale exercise will simulate the “cyber arena,” both actively engaging in electronic warfare and defending its networks.

The exercise was named for Meir Dagan, a former head of the Mossad intelligence service and former commander of the Northern Corps, who died last year.

They will be fighting against soldiers pretending to be Hezbollah terrorists, using “flags and enemy uniforms, fake weapons, fake explosive belts and more,” the army official said.

The costumes and props are part of a new army program known as “Red Containers,” which the officer said is a “breakthrough” for military simulation.

According to the official, this will be the “most significant” exercise in the history of the IDF Teleprocessing Corps, which is responsible for military communications, as the technological unit will “become the central headquarters” for directing the various units and branches of the military.

The number of reservists taking part in the drill is also “unprecedented,” the army officer said.

“The purpose of the large call-up of reservists is to prepare the reserve force for war in the northern arena and to adapt it to the changes and developing threats of recent years,” the official said.

The army also used the exercise to test a new contact system and ensure that it will work if needed in the future, the officer added.

For most units taking part in the exercise, including IDF Military Intelligence, it will be their largest in nearly 20 years, since a 1998 exercise known as “Gates of the Sky,” or “Shaare Shamayim.”

As part of the exercise, the regional divisions in the area will guard the communities in the north, carry out patrols, collect intelligence and build earthenware berms, the official said.

The IDF’s elite Yahalom combat engineering units will take part in the exercise, practicing disarming bombs, crossing waterways, uncovering hidden weapons caches and fighting in the types of tunnels that Hezbollah is believed to have dug in Lebanon.

The Artillery Corps and Combat Intelligence Corps will also use their respective drones in order to assist commanders on the ground, the official said.

In addition, the IDF Home Front Command will practice its “Safe Distance” plan, in which civilian populations along the Lebanese border will be evacuated farther south in order to keep them out of harm’s way, as the military believes that in a future conflict Hezbollah would try to send fighters to attack northern Israeli communities and their inhabitants.

“The decision to carry out the transfer of communities will be made at the political level, with the intention of preserving the safety of the citizens of the State of Israel,” the military official said.

The officer would not specify which communities would be evacuated during the exercise.

As the exercise will deal not only with offensive fighting, but also home front defense, the army will work alongside civilian emergency services, like the Israel Police, the Fire and Rescue Authority and the Magen David Adom ambulance service.

In addition to the dozens of ground forces brigades taking part, the military will also deploy aircraft and naval ships to the drill.

The navy will practice a number of scenarios that it expects will occur in war-time. Submarines, gun boats and patrol vessels will take part in the exercise, as will naval units on shore that monitor the coast for potential infiltration.

A naval officer, speaking on condition of anonymity, told The Times of Israel that the military fears Hezbollah will attempt to enter the country from the sea, using either ships, small submersibles, or scuba diving. The Iran-backed terrorist group is also believed to possess the Russian Yakhont missile, an advanced anti-ship weapon.

The air force, meanwhile, will practice bombing runs and close air support, as well as supplying troops on the ground with materiel and sending back intelligence so that ground forces can “maneuver on the front and behind enemy lines,” the army official said.

This will be the first large-scale exercise since the air force’s Hermes 900 unmanned aerial vehicle was declared operational last week.

In addition, the air force’s Aerial Defense Command will have its mettle tested, as the military expects thousands of rockets, missiles and mortars to rain down on Israel in a future conflict with Hezbollah. During the drill, the air force will operate its Iron Dome, Patriot, Arrow and David’s Sling systems, the official said.

Approximately 40 senior officers will monitor the exercise in order to assess the army’s capabilities, the officer said.

It took the military more than six months to prepare the “Light of the Grain” drill and the plans for it were personally approved by IDF Chief of Staff Gadi Eisenkot.

The 10-day exercise will in many ways serve as an answer to the difficulties faced by the military during the 2006 Second Lebanon War. The campaign saw intelligence failures and a breakdown in communication between different branches of the military. As such, information gathering and intra-army cooperation are two central aspects of “the Light of Grain.”