TEHRAN: Iran said on Saturday (Jan 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.
President Hassan Rouhani 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".
Canadian Prime Minister Justin Trudeau demanded Saturday that Iran provide "full clarity" on the downing of the plane, which Ottawa says had 57 Canadian citizens aboard.
"A full and complete investigation must be conducted," Trudeau said. "Iran must take full responsibility."
Iran's Supreme leader Ayatollah Ali Khamenei offered his condolences and ordered the armed forces to address "shortcomings" so that such a disaster does not happen again.
The acknowledgement came after officials in Iran denied for days Western claims that the Ukraine International Airlines plane had been struck by a missile in a catastrophic error.
The jet, which had been bound for Kiev, slammed into a field shortly after taking off from Tehran's Imam Khomeini International Airport before dawn on Wednesday.
The crash came hours after Iran launched missiles at bases hosting American forces in Iraq in response to the killing of top Iranian general Qasem Soleimani in a US drone strike.
On Saturday evening, police dispersed students who had converged on Amir Kabir University in Tehran to pay tribute to the victims, after some among the hundreds who gathered shouted "destructive" slogans, Fars news agency said.
State television reported that students shouted "anti-regime" chants, while Fars reported that posters of Soleimani had been torn down.
The aerospace commander of Iran's Revolutionary Guards accepted full responsibility for Wednesday's accident.
But Brigadier General Amirali Hajizadeh said the missile operator acted independently, targeting the Boeing 737 by mistaking it for a "cruise missile".
The operator failed to obtain approval from his superiors because of disruptions to a communications system, he said.
"He had 10 seconds to decide. He could have decided to strike or not to strike and under such circumstances he took the wrong decision."
"It was a short-range missile that exploded next to the plane," Hajizadeh added.
Iran had been under mounting international pressure to allow a "credible" investigation after video footage emerged appearing to show the moment the airliner was hit.
In footage that the New York Times said it had verified, a fast-moving object is seen rising into the sky before a bright flash appears. Several seconds later, an explosion is heard.
British Prime Minister Boris Johnston said Iran's acknowledgement was an "important first step", a line echoed by the German chancellor.
Iran's military was the first domestic institution to acknowledge the error, saying the aircraft had been mistaken for a "hostile target".
It said Iran had been at the highest level of alert after American "threats" and that the plane had turned and come close to a "sensitive" military site before it was targeted due to "human error".
Rouhani said Iran had been on alert for possible US attacks after Soleimani's "martyrdom".
"Iran is very much saddened by this catastrophic mistake and I, on behalf of the Islamic Republic of Iran, express my deep condolences to the families of victims of this painful catastrophe," the president said.
Rouhani added he had ordered "all relevant bodies to take all necessary actions (to ensure) compensation" to the families of those killed.
CALLS FOR TRANSPARENCY
The majority of passengers on Flight PS752 were Iranians and Canadians, including dual nationals, while Ukrainians, Afghans, Britons and Swedes were also aboard.
Rouhani told his Ukrainian counterpart Saturday that "all the persons involved in this air disaster will be brought to justice," Ukraine's presidency said.
President Volodymyr Zelensky said earlier on Facebook "we expect Iran ... to bring the guilty to the courts."
Sweden demanded a "complete and transparent probe" while Afghanistan said families of 13 of its citizens killed in the tragedy "deserve answers".
The disaster came as tensions soared in the region after Soleimani's killing, and fears grew of an all-out war between Iran and its arch-enemy the United States.
Washington said the Soleimani strike was carried out to prevent "imminent", large-scale attacks on American embassies.
Tehran had vowed "severe revenge" for his killing before launching missiles at the bases in Iraq.
Iran has invited the US, Ukraine, Canada and others to join the crash investigation.
It is Iran's worst civil aviation disaster since 1988 when the US military said it shot down an Iran Air plane over the Gulf by mistake, killing all 290 people on board.
The European Union's air safety agency on Saturday advised airlines to avoid flying over Iran.
"The recommendation in the current security climate is that overflight of Iran at all altitudes should be avoided until further notice, as a precautionary measure," the European Aviation Safety Agency said in a statement.
With nations around the world calling for restraint and de-escalation, fears of a full-blown conflict have subsided after US President Donald Trump said Iran appeared to be standing down after targeting the US bases in Iraq.