From the New York Times:

Iranian state television broadcast images of silos deep underground, saying they held medium- and long-range missiles ready to hit distant targets. The report showed footage of an underground launching pad for the Shahab-3 missile, which has a range of about 1,250 miles.

Col. Asghar Qelichkhani said the missiles were permanently in the vertical position and "ready to hit the predetermined targets." Last year, the International Institute for Strategic Studies in London reported "emerging evidence" of Iranian silos that could fire missiles at Iraq, Israel, Turkey and countries throughout the Persian Gulf. The commander of the Revolutionary Guards' Aerospace Force, Amir Ali Hajizadeh, said with these installations "we are certain that we can confront unequal enemies and defend the Islamic Republic of Iran."

Read more in the New York Times