The Iranian military launched a barrage of medium-range missiles on ISIS strongholds across eastern Syria Sunday night, in response to a double terror attack in Tehran earlier this month which left 17 dead and dozens more wounded.

According to a website of Iran’s Revolutionary Guard, the surface-to-surface missiles hit ISIS targets in the Deir Ez-Zour district in northeastern Syria, a rare direct intervention by forces in Iran in the Syrian civil war.

While Iran has supported the regime of Syrian President Bashar Assad and used its proxy, the Hezbollah terror group, to bolster Assad’s forces, Iran has largely refrained from attacking hostile forces in Syria directly.

On June 7th, terrorists struck two targets in Iran, killing a total of 17 people and wounding roughly 50.

ISIS has claimed responsibility for the attacks.

In response, the Iranian military pledged to strike back at those responsible for the attack.

"The spilling of any pure blood will not go unanswered," the Revolutionary Guard said via the Iranian news media outlet Tasnim.