Iran's Basij paramilitary force has held a two-day exercise in the capital, Tehran.
Some 50,000 members of the force took part in the drill, which culminated on September 3.
Basij spokesman General Nasser Shabani said the exercise was intended to "prove the security forces' ability to safeguard national security."
A senior commander, General Hossein Salami, hailed the force as the "eternal shield" protecting "the sacred system of the Islamic republic."
Established by the founder of the Islamic republic, Ayatollah Ruhollah Khomeini, the several-hundred-thousand-strong Basij played a key role in crushing opposition protests in 2009.
On September 2, members of the force unveiled an anti-American plaque at the gate of the former U.S. Embassy in Tehran.
The plaque carries a list of condemnations of America uttered by Khomeini.