In March 2019, the Iranian Revolutionary Guards Corps (IRGC) held a drill codenamed "Towards Jerusalem 1," near the strategic Strait of Hormuz. The IRGC flew about 50 "offensive and combat" drones in the Persian Gulf, including the "Saegheh" unmanned combat aerial vehicles based on the American RQ-170's, flying wing design.
The drones allegedly took off from bases between hundreds to more than 1,000 km from the targets on Bani Farur Island, and successfully bombed the targets. It was the first time such a high number of offensive drones participated in a drill.
The drill came as pressure mounts amid re-imposed US sanctions on Iran. Deputy Commander of IRGC, Brigadier General Hossein Salami said the United States' sanctions against Iran "bore fruit." He added that "Despite the empty and satanic dreams of the US and other ill-wishers of the Iranian nation, we witnessed tens of modern and advanced domestic RQ-170s and other types of combat drones in flight during a major drill and unique offensive operation". 
The drone project of Iran
The Iranian drone program was established during the Iran-Iraq War (1980-88). Despite years of sanctions and export restrictions, Iran has managed to develop and manufacture its own drones and possesses a range of surveillance and armed drones. Drones are considered a source of prestige of Iran as a state capable to develop its own modern military capabilities.
The ministry of intelligence and security MOIS, the IRGC, the country’s conventional military forces, and the Ministry of Defense, are the main players in Iran’s drone program.
Drones in general are deemed to be a ‘smart, accurate and inexpensive technology. The acquisition and introduction into service of armed drones led Iran to change its airpower doctrine.
The use of low-cost, low-risk tools such as drones is in line with Iran’s defense doctrine, which priorities asymmetrical warfare. Armed drones are viewed in Iran as a way to compensate for the vulnerabilities of its conventional air force.
Brigadier General Amir Ali Hajizadeh of the IRGC Aerospace Division said in a press conference in November 2018 that Iran had collected the US' General Atomics MQ-1 Predator and MQ-9 Reaper, as well as the smaller AAI RQ-7 Shadow (flown by the US Army and Marine Corps) and the Boeing/ Scan Eagle (flown by the US Navy as a shipboard reconnaissance drone) in addition to the RQ-170. The IRGC has also obtained an Israeli Elbit Hermes long-range drone. Iran has been accumulating captured US and Israeli drones and attempting to reverse-engineer them for years.
Iran primarily deploys surveillance and armed drones in its border areas, including for reconnaissance and target identification, as well as in neighboring countries in which Tehran is militarily involved like Iraq and Syria.
Iran aims at becoming a drone supplier and Iran might have supplied drones to Hezbollah, the Houthis in Yemen, Hamas, as well as the regime of Bashar Al-Assad in Syria.
" Iran holds drill near key strait, tests armed drones: report," Al Arabiya, March 14, 2019.
 Seth J Frantzman, "Iranian drones conduct massive 'way to Jerusalem' exercise – report," The Jerusalem Post, March 14, 2019.
 Sean Gallagher, Iran pumps up “massive” offensive exercise with as many as 50 drones, ARS Technica, March 14, 2019.