The Iranian government’s admission on Saturday that it shot down a Ukrainian commercial airliner triggered widespread protests nationwide attended by hundreds chanting slogans against the regime and the former head of its foreign terrorist organization, Qasem Soleimani.

An American airstrike eliminated Soleimani, officially the head of the Islamic Revolutionary Guard Corps (IRGC) Quds Force, in Baghdad this month. The IRGC is a U.S.-designated foreign terrorist organization; Soleimani led Iran’s terrorism operations abroad and was particularly active in Iraq and Syria against American soldiers.

Iranian officials claimed that the strike against Soleimani resulted in an unknown Iranian soldier shooting down Ukraine International Airlines (UIA) Flight 752 early Wednesday as Tehran shot over a dozen ballistic missiles at U.S. targets in Iraq, a move meant as a response to Soleimani’s demise. Iran had previously claimed a mechanical error had doomed the flight, where all 176 people on board died, and accused the United States of spreading the “false” rumor that the Iranian military shot a Russian Tor missile at it shortly after takeoff to “manipulate stock markets.”

Fars News Agency, an Iranian regime propaganda outlet, has not retracted an article making that claim on its English-language website at press time despite Iranian military officials admitting they shot the plane.

Fars reported on Monday that hundreds of Iranians – a crowd of up to 1,000 in Tehran – responded to the news with protests. The Iranian people entered Saturday already mourning the death of over 50 people in a stampede at a mandatory funeral for Soleimani. NBC News identified at least five other major urban centers – Isfahan, Hamadan, Sari, Rasht, and Babol – as also experiencing protests. Many congregated around university campuses.

The crowds, images of which appeared on social media Saturday, chanted slogans against the regime, urging Supreme Leader Ayatollah Ali Khamenei to step down and tearing up photos of Soleimani. Videos reportedly showed “death to the Islamic Republic” and “death to the dictator” among the chants.

Another round of #IranProtests ; in front of Tehran polytechnic university; “Death to the Islamic republic, down with @Khamenei_fa “ pic.twitter.com/9XUvLmZfbU — Ali Hamedani (@BBCHamedani) January 11, 2020

Al-Arabiya, a Saudi outlet, posted several videos of the protests online in which crowds appear to chant “Soleimani is a murderer,” “don’t be afraid,” and “we’re all together” in Farsi. At least one video also appeared to show the dissemination of tear gas to disperse the crowds.

The governments of Saudi Arabia and Iran are regional enemies and Iranian regime officials forced crowds to chant “death to al-Saud,” the Saudi royal family, during Soleimani’s funeral.

“Don’t be afraid, don’t be afraid, we’re all together,” protesters chant at Amir Kabir University in Tehran against the regime after Iran’s Revolutionary Guard acknowledged that it accidentally shot down the Ukrainian jetliner.https://t.co/muQwHKWqUu pic.twitter.com/q3YcN0kufr — Al Arabiya English (@AlArabiya_Eng) January 11, 2020

“Soleimani is a murderer, and his leader (Khamenei) is also a murderer,” protesters in Tehran, Iran, chant as activists say demonstrations are spreading to other cities like Isfahan and Shiraz.https://t.co/muQwHKWqUu pic.twitter.com/F6BrrN2HK5 — Al Arabiya English (@AlArabiya_Eng) January 11, 2020

The protesters also participated in candlelit vigils for the dead and shamed Iranian authorities for killing them, reportedly chanting “dishonorable” and “resignation is not enough,” according to Radio Free Europe/Radio Liberty (RFE/RL).

Prior to taking the streets after the revelation of the alleged truth behind the fate of the UIA flight, Iranians had already reportedly begun to mock their government online. While the ballistic missile strikes against Iraqi military bases housing U.S. troops on Wednesday failed to cause any casualties or non-negligible property damage, Iranian state media claimed that the missiles killed 80 Americans and devastated American operations in the Middle East. According to Radio Farda, the Iranian wing of RFE/RL, Fars News Agency also claimed that Iran shot 15 missiles and destroyed 20 American targets, which triggered derision in the few online avenues Iranians have access to express themselves on.

“Does the informed source know math? How could they blow up 20 spots with 15 missiles? Did the missiles reproduce on the way or pollinate? For God’s sakes, where are we living?” one Iranian user reportedly asked on Twitter.

Iranian state media outlets revealed the arrest of Britain’s Ambassador to Iran Robert Macaire amid the protests, reportedly present at a manifestation at Amir Kabir University in Tehran.

“Britain’s envoy to Tehran Rob Macaire was arrested for hours for his involvement in provoking suspicious acts in a gathering held in front of Tehran Amir Kabir University on Saturday,” Iran’s Tasnim news agency stated. “He is accused of involvement in provoking some radical acts among protesters. He was freed a few hours later but will be summoned tomorrow for further explanations.”

President Donald Trump responded to the protests on Saturday by posting a message on Twitter in both Farsi and English supporting them.

“To the brave, long-suffering people of Iran: I’ve stood with you since the beginning of my Presidency, and my Administration will continue to stand with you. We are following your protests closely, and are inspired by your courage,” President Trump wrote. The Farsi language post has reportedly broken Twitter engagement records in that language.

The Iranian armed forces posted a statement on Saturday simultaneously admitting responsibility for the mass killing of the UIA flight passengers and blaming President Trump for their deaths.

“Following the threats from the president and the military commanders of the criminal US that a large number of targets on the Islamic Republic of Iran’s soil would be hit in case of a retaliatory operation, and considering an unprecedented increase in the aerial movements over the region, the Islamic Republic of Iran’s Armed Forces were on the highest level of readiness in order to respond to possible threats,” the statement read.

Foreign Minister Mohammad Javad Zarif blamed “Human error at time of crisis caused by US adventurism” for the attack on the commercial flight. Fars News Agency published a story allegedly quoting the family of one of the Iranians killed on the flight thanking the IRGC for their “good will” and praising Soleimani.

Amirali Hajizadeh, the head of the aerospace division of the Islamic Revolutionary Guards Corps (IRGC), told reporters on Saturday that, upon hearing that Iranian military forces shot down the civilian aircraft, “I wished I was dead so I wouldn’t have to see such an accident.”

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