Iran admits its troops shot down a passenger jet and killed 176 people due to a string of colossal failures

A new report from Iran's Civil Aviation Organization reveals that a string of massive failures led Iran's military to shoot down a passenger jet and kill 176 people earlier this year.

The Iranian military shot down Ukraine International Airlines Flight 752 in January due to human error, an improperly calibrated air defense system, communication problems, and a breach of engagement protocols, the Iranian report says.

Following the release of the report, Ukraine said that it is not yet ready to accept Iran's explanation for what happened.

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A chain of serious mistakes led Iranian troops to fire on a passenger jet earlier this year, killing 176 people, a new report from Iran's Civil Aviation Organization reveals.

The Iranian military shot down Ukraine International Airlines Flight 752 in January due to human error, an improperly calibrated air defense system, communication problems, and a breach of engagement protocols, specifically firing without authorization, the report says.

The flight went down shortly after takeoff from Imam Khomeini International Airport on Jan. 8. While Iran initially claimed engine failure was to blame, it admitted days later, following reported foreign intelligence on the actual cause, that the passenger aircraft was shot down by a pair of surface-to-air missiles.

The downing of Flight 752 happened just hours after the Iranian military fired more than a dozen ballistic missiles at US and coalition troops in Iraq in retaliation for the US drone strike one week earlier that eliminated top Iranian general and Islamic Revolutionary Guard Corps commander Gen. Qassem Soleimani.

In the days that followed, the IRGC admitted that it was on high alert at the time Flight 752 was shot down, with one commander stating that Iran was "totally prepared for a full-fledged war."

Debris from the crash of Flight 752 Reuters

In that heightened state of alert, the report from Iran's Civil Aviation Organization explains, responsibility for air traffic control was transferred from civilian authorities to the military, which cleared Ukraine International Airlines Flight 752 to takeoff for its return trip to Kyiv.

Once in the air, though, Flight 752 "was identified by one of the air defense units as a threat and targeted consequently," the new report said.

An air defense system that was moved was not recalibrated for its new position due to "human error" and was 107 degrees off, a major mistake that made it appear a passenger jet ascending from Tehran's aiport was a potential military target seemingly approaching the capital from the southwest. The report noted that "such a failure initiated a hazard chain."

The air defense unit operator relayed the information to the coordination center, but, for reasons not presented in the report, the notification was not communicated successfully.

The operator, who was reportedly unaware of the calibration issue, then independently analyzed the information and concluded that the detected target was a threat.

Without receiving authorization from the coordination center, the air defense unit operator opened fire on the aircraft, a violation of procedure. Two missiles were fired.

The passenger jet caught fire after it was hit and turned right toward the airport before crashing into a playground. The plane reportedly exploded when it hit the ground.

"The aircraft," the report said, "then kept hitting the ground and bouncing on a route towards the airport, making the aircraft pieces, victims' properties, objects and body remains disintegrate completely in a vast area."

Ukraine's foreign minister said Tuesday that the country still has a lot of unanswered questions and is not yet ready to accept Iran's explanation.

"I want to clearly emphasise: it is early to say that the plane was shot down as a result of human error, as the Iranian side claims," Foreign Minister Dmytro Kuleba said Tuesday. He added that "we have many questions, and we need a large number of authoritative, unbiased, objective answers about what happened."

He insisted that Ukraine "will do all we can so that Iran pays the highest price" for what happened. Iran has reportedly agreed to compensate the families of victims for their loss.

The report from Iran's Civil Aviation Organization said the country had learned its lesson and that the likelihood of a repeat of the Flight 752 tragedy was "improbable."