The incident came hours after Iran launched a wave of missiles at Iraqi bases housing American troops in retaliation for the killing of Qasem Soleimani, one of Iran's top generals, in a US drone strike.

The Iranian armed forces were first to acknowledge the error, saying the Boeing 737 had been mistaken for a "hostile target" at a time when enemy threats were at the highest level.

Following are the main elements from the five-point statement:

The armed forces said it had opened an investigation into what it called the "heartbreaking incident" after the Ukraine International Airlines plane (UIA) was brought down on Wednesday.

1. The Iranian armed forces had been on their highest level of alert after launching missiles at Iraqi bases housing US troops and following "threats by the criminal American president and military commanders".

2. Flights by the US military had increased around Iran after the missile operation and following some reports of aerial targets moving towards "strategic centres" in the Islamic republic.

3. After taking off from Tehran's Imam Khomeini International Airport, UIA flight PS752 turned, got close to a "sensitive military site" of the Revolutionary Guards and appeared to fly like a "hostile target". Due to "human error", the plane was hit, which "unfortunately led to the martyrdom of a number of our dear compatriots and loss of life of a number of foreign nationals".

4. The statement expressed "condolences and sympathy" with the families of those who died and gave an assurance that a "repetition of such mistakes would become impossible" through changes in operational procedures. It also said the armed forces would immediately present the "culprit" to the judiciary.

5. Finally, it said "relevant officials from the Revolutionary Guards should, as soon as possible, give detailed explanations to the honourable people in the national media".

afp

BOEING