Pressure continues to pile on the Iranian regime as furious anti-government protesters take to the streets for a second day and newspapers join the calls for justice over the military’s “unintentional” shooting down of the Ukrainian passenger flight.

Thousands of protesters braved the threat of violent repression or incarceration amid a heavy riot police presence in several cities, many demanding the resignation of president Hassan Rouhani and criticising Supreme Leader Ali Khamenei with chants of “death to the dictator."

In Tehran, sizeable crowds overcame authorities’ efforts to block off Azadi (Freedom) Square. Security forces later resorted to tear gassing those assembled there. Some violence broke out in the square as special forces and militia members attacked protesters and fired rubber bullets.

Their fury was further amplified on Sunday as Iran’s moderate daily newspaper Etemad ran a headline saying those responsible for the plane crash – which killed 176 people – and the subsequent cover-up, should “apologise and resign”. The paper called this “the people’s demand”.

The tragic incident, and the regime’s handling of it, appears to have subdued the outpouring of national unity which followed the Trump-ordered assassination of top general Qassem Soleimani.

Iran plane crash: Tehran admits accidentally shooting Boeing 737 Show all 25 1 /25 Iran plane crash: Tehran admits accidentally shooting Boeing 737 Iran plane crash: Tehran admits accidentally shooting Boeing 737 People standing and analysing the fragments and remains of the Ukraine International Airlines plane Boeing 737-800 that crashed outside the Iranian capital Tehran on January 8 National Security and Defense Council of Ukraine/AFP Iran plane crash: Tehran admits accidentally shooting Boeing 737 A hole in a part of Ukraine International Airlines Flight PS752 Iran said on January 11, it "unintentionally" shot down a Ukrainian passenger jet, killing all 176 people aboard, in an abrupt about-turn after initially denying Western claims it was struck by a missile Ukrainian Presidential Press Service/EPA Iran plane crash: Tehran admits accidentally shooting Boeing 737 Tehran Iranians protested in front of the Amir Kabir University in Tehran after the Iranian military released their statement about the flight EPA Iran plane crash: Tehran admits accidentally shooting Boeing 737 Debris of the wreckage Iranian president said a military probe into the tragedy had found "missiles fired due to human error" brought down the Boeing 737, calling it an "unforgivable mistake" National Security and Defense Council of Ukraine/AFP Iran plane crash: Tehran admits accidentally shooting Boeing 737 Tehran Local newspapers in Tehran carrying headlines such as: "National Mourning", "Apologize, Resign", "Unforgivable", "Great Disaster" ... concerning the downed Ukranian jetliner AFP via Getty Iran plane crash: Tehran admits accidentally shooting Boeing 737 Kiev, Ukraine Ukraine International Airlines President Yevhenii Dykhne stands next to a map of flight PS-752's departure path at a news briefing about the crash Reuters Iran plane crash: Tehran admits accidentally shooting Boeing 737 Tehran The Iranian students demonstrated following a tribute for the victims AFP via Getty Iran plane crash: Tehran admits accidentally shooting Boeing 737 The Canadian passport of a victim This handout photograph taken and released on January 11, 2019, by The National Security and Defense Council of Ukraine, shows the Canadian passport of avictim of the Ukraine International Airlines plane Boeing 737-800 that crashed outside the Iranian capital Tehran on January 8, 2020. - Iran said on January 11, 2020 it "unintentionally" shot down a Ukrainian passenger jet, killing all 176 people aboard, in an abrupt about-turn after initially denying Western claims it was struck by a missile. Iranian president said a military probe into the tragedy had found "missiles fired due to human error" brought down the Boeing 737, calling it an "unforgivable mistake". (Photo by STR / National Security and Defense Council of Ukraine / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / National Security and Defense Council of Ukraine" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS (Photo by STR/National Security and Defense Co/AFP via Getty Images) STR National Security and Defense Council of Ukraine/AFP Iran plane crash: Tehran admits accidentally shooting Boeing 737 This combination of satellite pictures shows a before and after image of the crash site in Tehran The image (top), according to Maxar, shows vehicles and personnel (centre) during accident recovery and investigation on January 11, with a wall by the soccer pitch (left) destroyed as well as a wall (top right). The image below was taken on November 27, 2019 Maxar Technologies/AFP Iran plane crash: Tehran admits accidentally shooting Boeing 737 Ukraine The portraits of victims with flowers and candles at Boryspil International Airport in Kiev EPA Iran plane crash: Tehran admits accidentally shooting Boeing 737 Holes in the wreckage This handout photograph taken and released on January 11, 2019, by The National Security and Defense Council of Ukraine, shows holes in the wreckage of the Ukraine International Airlines plane Boeing 737-800 that crashed outside the Iranian capital Tehran on January 8, 2020. - Iran said on January 11, 2020 it "unintentionally" shot down a Ukrainian passenger jet, killing all 176 people aboard, in an abrupt about-turn after initially denying Western claims it was struck by a missile. Iranian president said a military probe into the tragedy had found "missiles fired due to human error" brought down the Boeing 737, calling it an "unforgivable mistake". (Photo by STR / National Security and Defense Council of Ukraine / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / National Security and Defense Council of Ukraine" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS (Photo by STR/National Security and Defense Co/AFP via Getty Images) STR National Security and Defense Council of Ukraine/AFP Iran plane crash: Tehran admits accidentally shooting Boeing 737 Tehran People gathered for a candlelight vigil at the gate of Amri Kabir University AP Iran plane crash: Tehran admits accidentally shooting Boeing 737 People standing and analysing the fragments and remains of the Ukraine International Airlines plane This handout photograph taken and released on January 11, 2019, by The National Security and Defense Council of Ukraine, shows people standing and analysing the fragments and remains of the Ukraine International Airlines plane Boeing 737-800 that crashed outside the Iranian capital Tehran on January 8, 2020. - Iran said on January 11, 2020 it "unintentionally" shot down a Ukrainian passenger jet, killing all 176 people aboard, in an abrupt about-turn after initially denying Western claims it was struck by a missile. Iranian president said a military probe into the tragedy had found "missiles fired due to human error" brought down the Boeing 737, calling it an "unforgivable mistake". (Photo by STR / National Security and Defense Council of Ukraine / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / National Security and Defense Council of Ukraine" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS (Photo by STR/National Security and Defense Co/AFP via Getty Images) STR National Security and Defense Council of Ukraine/AFP Iran plane crash: Tehran admits accidentally shooting Boeing 737 Protests against war with Iran took place in London The demonstration was co-organized by the Campaign For Nuclear Disarmament and the Stop the War Coalition, an activist group formed in 2001 Getty Iran plane crash: Tehran admits accidentally shooting Boeing 737 A hole in a part of Ukraine International Airlines Flight epa08119576 An undated handout picture provided by the Ukrainian Presidential Press Service allegedly shows a hole in a part of Ukraine International Airlines Flight PS752, issued on 11 January 2020. According to media reports on 11 January 2020, the Iranian military released a statement claiming that Ukraine International Airlines flight PS752 was shot down due to 'human error.' The Ukrainian jet, flying from Tehran, Iran, to Kiev, Ukraine, crashed minutes after takeoff on 08 January 2020, killing all 167 passengers and nine crew members aboard. EPA/UKRAINE PRESIDENTIAL PRESS SERVICE HANDOUT BEST QUALITY AVAILABLE HANDOUT EDITORIAL USE ONLY/NO SALES UKRAINE PRESIDENTIAL PRESS SERVICE HANDOUT Ukrainian Presidential Press Service/EPA Iran plane crash: Tehran admits accidentally shooting Boeing 737 Labour Party leader spoke at the event Jeremy Corbyn posing with an anti-war banner during the demonstration against the threat of war on Iran, in Trafalgar Square AFP via Getty Images Iran plane crash: Tehran admits accidentally shooting Boeing 737 A rose rests on a page featuring photographs of people who died in Iran Iranian Americans from across California converged in Los Angeles to participate in the California Convention for a Free Iran Reuters Iran plane crash: Tehran admits accidentally shooting Boeing 737 A young boy protests against a possible war with Iran in London A young protester at a Campaign for Nuclear Disarmament demonstration against a possible war with Iran in Trafalgar Square, central London. PA Photo. Picture date: Saturday January 11, 2020. See PA story POLITICS Iran. Photo credit should read: Jonathan Brady/PA Wire Jonathan Brady PA Iran plane crash: Tehran admits accidentally shooting Boeing 737 Holes in the wreckage This handout photograph taken and released on January 11, 2019, by The National Security and Defense Council of Ukraine, shows holes in the wreckage of the Ukraine International Airlines plane Boeing 737-800 that crashed outside the Iranian capital Tehran on January 8, 2020. - Iran said on January 11, 2020 it "unintentionally" shot down a Ukrainian passenger jet, killing all 176 people aboard, in an abrupt about-turn after initially denying Western claims it was struck by a missile. Iranian president said a military probe into the tragedy had found "missiles fired due to human error" brought down the Boeing 737, calling it an "unforgivable mistake". (Photo by STR / National Security and Defense Council of Ukraine / AFP) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / National Security and Defense Council of Ukraine" - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS (Photo by STR/National Security and Defense Co/AFP via Getty Images) STR National Security and Defense Council of Ukraine/AFP Iran plane crash: Tehran admits accidentally shooting Boeing 737 Rescue workers search the scene on January 8 In this Wednesday, Jan. 8, 2020, photo, rescue workers search the scene where a Ukrainian plane crashed in Shahedshahr, southwest of the capital Tehran, Iran. Iran on Saturday, Jan. 11, acknowledged that its armed forces "unintentionally" shot down the Ukrainian jetliner that crashed earlier this week, killing all 176 aboard, after the government had repeatedly denied Western accusations that it was responsible. (AP Photo/Ebrahim Noroozi) Ebrahim Noroozi AP Iran plane crash: Tehran admits accidentally shooting Boeing 737 Rescue workers search the scene In this Wednesday, Jan. 8, 2020 photo, rescue workers search the scene where a Ukrainian plane crashed in Shahedshahr, southwest of the capital Tehran, Iran. Iran on Saturday acknowledged that its armed forces "unintentionally" shot down the Ukrainian jetliner that crashed earlier this week, killing all 176 aboard, after the government had repeatedly denied Western accusations that it was responsible. (AP Photo/Ebrahim Noroozi) Ebrahim Noroozi AP Iran plane crash: Tehran admits accidentally shooting Boeing 737 Debris of the Ukraine International Airlines General view of the debris of the Ukraine International Airlines, flight PS752, Boeing 737-800 plane that crashed after take-off from Iran's Imam Khomeini airport, on the outskirts of Tehran, Iran January 8, 2020 is seen in this screen grab obtained from a social media video via REUTERS THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. MANDATORY CREDIT. SOCIAL MEDIA Reuters Iran plane crash: Tehran admits accidentally shooting Boeing 737 Debris of the Ukraine International Airlines (FILES) In this file photo taken on January 8, 2020 rescue teams are seen at the scene of a Ukrainian airliner that crashed shortly after take-off near Imam Khomeini airport in the Iranian capital Tehran. - Iran said on January 11 that it unintentionally shot down the Ukrainian plane due to 'human error'. (Photo by Akbar TAVAKOLI / IRNA / AFP) (Photo by AKBAR TAVAKOLI/IRNA/AFP via Getty Images) AKBAR TAVAKOLI IRNA/AFP/Getty Iran plane crash: Tehran admits accidentally shooting Boeing 737 One of the engines of the plane lies among the wreckage epa08118590 (FILE) - One of the engines of the plane lies among the wreckage after a Ukraine International Airlines Boeing 737-800 carrying 176 people crashed near Imam Khomeini Airport in Tehran, killing everyone on board, in Shahriar, Iran, 08 January 2020 (reissued 11 January 2020). According to media reports, the Iranian military released a statement on 11 January claiming that Ukraine International Airlines flight 752 was shot down due to a human error. EPA/ABEDIN TAHERKENAREH ABEDIN TAHERKENAREH EPA Iran plane crash: Tehran admits accidentally shooting Boeing 737 Debris of the Ukraine International Airlines FILE - In this Jan. 8, 2020, photo, debris is seen from an Ukrainian plane which crashed as authorities work at the scene in Shahedshahr, southwest of the capital Tehran, Iran. Iran announced Saturday, Jan. 11, that its military â€œunintentionallyâ€ shot down the Ukrainian jetliner that crashed earlier this week, killing all 176 aboard, after the government had repeatedly denied Western accusations that it was responsible. (AP Photo/Ebrahim Noroozi, File) Ebrahim Noroozi AP

In contrast to the anti-US sentiment displayed during Soleimani’s vast memorial proceedings, social media footage showed protesters taking pains not to step on American and Israeli flags painted on a walkway, with others chanting: “Our enemy is right here, they are lying that it’s America.”

Iranian officials will fear a resurgence of the widespread protests that raged in the months before Soleimani’s killing, thought to be the largest since the 1979 Islamic Revolution.

Sparked by opposition to a fuel price hike amid dangerously punitive US sanctions, the protests grew into a major revolt against corruption, poverty and the regime’s incorrigible nature.

The government’s brutal attempts at repression are believed to have taken the lives of between 300 and 1,500 people, but an internet shutdown obscured much about the protests, including their death toll.

On Sunday morning, despite only numbering in their hundreds, dissidents gathered at university campuses in several cities, including Isfahan, while calls circulated for larger protests later in the day.

In addition to black-suited riot police, Revolutionary Guard members patrolled the capital on motorbikes in an apparent effort to deter the sizeable protests that would eventually emerge, while plain-clothes security forces also monitored the streets.

The demonstrators’ efforts and bravery were lauded by Donald Trump, who launched a brazen attempt to paint himself as an ally of the Iranian people – and further undermine the country’s leadership – days after pushing the country to the brink of conflict and threatening to commit war crimes by destroying Iranian cultural sites.

“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,” Mr Trump tweeted in Farsi.

“The government of Iran must allow human rights groups to monitor and report facts from the ground on the ongoing protests by the Iranian people. There can not be another massacre of peaceful protesters, nor an internet shutdown. The world is watching.”

While his call for human rights to be observed were welcomed, the US president was also accused of gross hypocrisy.

“Only on planet Trump can you ban Iranians from visiting their family in the US, deny them access to life-saving drugs, threaten to bomb their cultural heritage, and then claim that you are in solidarity with them,” said London School of Economics’ Roham Alvandi, an associate professor of international history specialising in Iran.

Trump's defence secretary Mark Esper admits he 'didn't see' evidence of imminent threat from Iran

Meanwhile, the leader of Iran’s Revolutionary Guards, Hossein Salami, apologised profusely for his forces shooting down Ukraine International Airlines flight 752, saying: “I have never been so ashamed in my life.

“I would have liked to have been in that plane and to have crashed and burned with them rather than bear witness to this tragic event.”

But Mr Khamenei, the country’s supreme leader, blamed the region’s turbulence on “the corruptive presence of the US and its cohorts” during a visit from Qatar’s visiting ruler, Emir Sheikh Tamim bin Hamad al-Thani. Mr Khamenei urged greater cooperation between Middle Eastern nations as “the only way to deal with it”.

It came hours after US defence secretary Mark Esper admitted he “didn’t see” the evidence of imminent threats to four US embassies claimed by Mr Trump as justification for killing Soleimani.

European leaders sustained their efforts to contain the fallout from the Quds force commander’s killing on Sunday, with Boris Johnson, France’s Emmanuel Macron and Germany’s Angela Merkel issuing a joint statement urging Iran to return to full compliance with the 2015 nuclear deal.

However, the protests in Tehran also inadvertently saw UK-Iranian relations take a sour turn, after the British ambassador Rob Macaire was briefly arrested at the protests on Saturday, which began as a vigil.

The UK said its envoy was detained “without grounds or explanation” and in “flagrant violation of international law”.

Condemning the arrest, foreign secretary Dominic Raab said Iran “can continue its march towards pariah status ... or take steps to de-escalate tensions and engage in a diplomatic path forwards”.

Iran’s deputy foreign minister Abbas Araghchi later tweeted that Mr Macaire was arrested “as an unknown foreigner in an illegal gathering” and was released when authorities realised who he was.

A member of Iran’s parliamentary committee on national security and foreign policy, Alaeddin Boroujerdi, accused the ambassador of organising protests and called for his expulsion.

A small group of Iranians later gathered outside the British Embassy, chanting “death to England” and calling for the ambassador’s expulsion and the embassy’s closure. Police stood guard outside the facility.

Iranian media, meanwhile, focused on the regime’s admission of responsibility for the crash, with several newspapers calling for those responsible to apologise and resign.

The hardline daily Vatan-e Emrooz bore the front-page headline ”A sky full of sadness”, while the Hamshahri daily went with “Shame”, and the Iran daily said “Unforgivable.”