Iran's Revolutionary Guards test-fired several ballistic missiles from silos across the country as part of a military exercise on Tuesday, the Iranian Students news agency (ISNA) reported.The test was intended "to show Iran's deterrent power and also the Islamic Republic's ability to confront any threat against the (Islamic) Revolution, the state and the sovereignty of the country", ISNA said.Iran continued development of their Emad ballistic missiles in spite of the fact that it has evoked a harsh response from the US. In January, the US imposed fresh sanctions on the Islamic Republic on the grounds that the Emad is capable of carrying a nuclear warhead and the test therefore violated a UN resolution. Iran asserted that broadening its ballistic missile arsenal is a critical component of its deterrence program. The country’s current missile program focuses on improving the precision, range and payload opportunities of the weapons.Iran revealed its missile silo in October 2015 on Iranian state television in a demonstration of its Emad missiles, only several months after the approval of the controversial nuclear deal, formally known as the Joint Comprehensive Plan of Action. The deal explicitly extended its arms embargo and ballistic missile technology ban on Iran for eight years.In sharp contrast to the stringent restrictions renewed by the nuclear deal, the Iranians do not seem to be deterred as the Revolutionary Guards’ second- in-command, Brigadier General Hossein Salami, said last month that Iran’s depots and underground facilities are so full that they do not know how to store their new missiles.Michael Wilner contributed to this report.