Islamic State terrorists struck at the heart of the Islamic Republic of Iran Wednesday in a complex attack, part of which was broadcasted minutes after by the terrorist group’s official news agency.

WATCH: (WARNING: GRAPHIC)

The terrorist is heard shouting “Thank God! Do you think that we are going to leave? We will remain here, God willing,” throughout the video.

The attack killed 12 and injured dozens more as two pairs of terrorists made their way through Iran’s parliament building, and struck the shrine of deceased Iranian Supreme Leader Ayatollah Khoemeni. The attack marks the first successful attempt by the terrorist group in Iran.

WATCH: (WARNING: GRAPHIC)

ISIS suicide bomber detonates himself at Imam Khomeini shrine south of Tehran. #pt pic.twitter.com/Vb0CPh2SGA — Hayder al-Khoei (@Hayder_alKhoei) June 7, 2017

Iranian security forces sought to take down the terrorists inside the parliament building but were unable to contain the situation quickly. One attacker broke through the building siege an hour into the attack and ran around nearby streets shooting as many as possible before blowing himself up. Footage of the attacker’s return surfaced on social media.

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