The Iranian Revolutionary Guards has fired ground-to-ground missiles from western Iran into eastern Syria, aiming at the bases of militant groups Iran holds responsible for attacks in Tehran which left 18 dead last week, the Tasnim news agency reported.

>> UPDATE: Iran's Missile Attack on Syria Failed: 5 Missed, 3 Landed in Iraq

This was the first operational use of mid-range missiles by Iran since the war with Iraq, which ended in 1988.

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The Iranian video is currently under examination by Israel, in attempt to understand the details of the incident. It remains unknown if the missiles struck their targets and what effect the strikes could have on the region.

Video footage purports to show impact of Iranian missile strike in Syria.

"The spilling of any pure blood will not go unanswered," the Revolutionary Guards said in a statement, according to Tasnim.

The Guard's website, as well as semi-official news agencies, reported the strikes Sunday on Deir el-Zour, Syria. The Guard's website said it launched surface-to-surface medium-range missiles targeting the area.

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It did not immediately offer other specifics, other than to say the missiles were launched from Iran.

A Guard statement carried on its website said the strike came from its bases in western Iran. It said many "terrorists" were killed and their weapons had been destroyed in the strike.

The paramilitary force warned Islamic State militants and their "regional and international supporters" that similar retaliatory attacks would target them as well if another assault in Iran occurs.

Activists in Syria did not immediately have information about the Iranian-claimed strikes. Deir el-Zour is home to both Islamic State militants and civilians.

Five Islamic State-linked attackers stormed Iran's parliament and a shrine to revolutionary leader Ayatollah Ruhollah Khomeini this month, killing at least 18 people and wounding more than 50.

Meanwhile, the Syrian army said that the U.S.-led coalition shot down one of its planes near the ISIS-stronghold of Raqqa. No other details were given.