“The two black boxes of the Ukranian 737 aeroplane that crashed this morning have been found,” said the authority’s spokesman, Reza Jafarzadeh, according to semi-official news agency Isna.

The Ukrainian jet bound for Kiev slammed into a field before dawn at Khalaj Abad, about 45km northwest of Imam Khomeini International Airport.

None of the 176 people on board survived, Iranian officials said.

The plane belonged to Ukraine International Airlines, which said the Boeing 737 involved in the crash had been built in 2016 and was checked only two days before it went down.

Preliminary statements by Iranian and Ukrainian authorities suggest the plane suffered an engine malfunction, though the airline did not detail any reasons for the accident.

The crash came shortly after Iran said it fired missiles at Iraqi bases in revenge for the killing of one of the Islamic republic’s top military commanders in a US drone strike on Friday.

Following the missile strikes, the US Federal Aviation Administration said it was banning US-registered carriers from flying over Iraq, Iran and the Gulf after rocket attacks on US forces in Iraq.

Other international carrier said they were suspending all routes passing through Iraqi or Iranian airspace.