At least 12 people were killed and 43 wounded in simultaneous attacks on Iran's Parliament building and the mausoleum of the republic's founder Ayatollah Khomeini on June 7. Iran's Revolutionary Guards have blamed Saudi Arabia supported ISIS militants for the attacks. The allegation will likely infuriate Saudi Arabia amid simmering regional tensions. The attack is the most audacious one to hit Tehran in decades.

What happened? How the attack on the parliament unfolded Credits:

At least six attackers were involved in the simultaneous assault. At around 10 am local time, gunmen apparently dressed as women, stormed into the parliament and opened fire. The gunmen took several hostages and at least one attacker detonated a suicide bomb. Security forces killed all four gunmen after a four hour operation, bringing the situation under control.

Information Mausoleum attacked by suicide bomber and gunman

Ayatollah Khomeini's mausoleum, located around 25-km away from the parliament, witnessed a shooting spree and a suicide bombing. Security personnel arrested an attacker at the tomb, according to local news.

ISIS role ISIS claims responsibility for the attack on parliament and mausoleum

ISIS has claimed responsibility for the attacks, according to a statement on its Amaq news agency. Sunni jihadi groups such as ISIS have singled out Shia Iran as a target. The Sunni groups consider Shias as apostates. In March, ISIS had warned it "will conquer Iran and restore it to the Sunni Muslim nation as it was before."

Angry exchange Iran denounces Trump's condolence message as "repugnant"

Following the attacks, US President Donald Trump said he prayed for victims but slammed Iran by adding, "states that sponsor terrorism risk falling victim to the evil they promote." Iran's Foreign Minister Javad Zarif responded on twitter: "Repugnant White House statement .... Iranian people reject such US claims of friendship." Iran's Revolutionary Guards also tied the attack to Trump's recent visit to Saudi Arabia.

Aftermath Attack has left largely safe Tehran shocked Credits: