A newly released recording reportedly shows that Iranian officialsknew a missile had brought down a Ukrainian passenger airplane last month.The plane crashed shortly after leaving Tehran, killing all 176 people on the jet.Sunday night, a Ukrainian television station broadcast what it saidwas a recording of an exchange between Iranian air traffic controllers and an Iranian pilot.Ukrainian President Volodymyr Zelensky confirmed the authenticity of the recording.Iran reacted on Monday.The head of the Iranian team investigating the crash, Hassan Razaeifar,said he believed the recording was real.He admitted that the recording had been given to Ukrainian officials.But he condemned its release to the media, calling the act "unprofessional."The Mehr news agency reported that Rezaeifarsaid the release made Iran not want to give the Ukrainians any more evidence.Iran's civilian government denied for days after the January 8 crashthat it knew who had shot down the aircraft.The aircraft was struck hours after Iran's Revolutionary Guard launched ballistic missilesin an attack on Iraqi bases that housed United States forces.It was Iran's reaction to an American drone aircraftkilling a top Iranian general, Qassem Soleimani, in Baghdad.Soleimani was the top general of the Guard's Quds Force.The Associated Press notes that the Guard is answerableonly to Iran's top religious leader, Ayatollah Ali Khamenei.Ukrainian television channel Ukrainian 1+1 published a written version of the recording.It contains an exchange between an air-traffic controller and a pilot for Iran's Aseman Airlines.His plane reportedly was flying near Tehran at the time of the attack."A series of lights like...yes, it's a missile, is there something?" the pilot calls out to the controller."No, how many miles? Where?" the controller asks.The pilot then says, "It is the light of a missile."He later says that he saw an explosion."It was an explosion. We saw a very big light there,I don't really know what it was," the pilot goes on to say.Publicly available radar information suggests that people on the Aseman Airlines flightwere close enough to Tehran to see the explosion.For several days, civilian aviation officials in Iran said a missile did not bring down the plane.At the same time, Canadian Prime Minister Justin Trudeauand U.S. officials said it appeared that the plane had been shot down.Ukraine's president told the television station that, "The recording, indeed,shows that the Iranian side knew from the start that our plane was shot down by a missile."Zelensky again asked Iran to send the plane's flight recorders to Kyiv.Iranian officials promised to do so last month but have not yet done so.On Monday, Ukrainian investigators were to travel to Tehranto take part in the process of decoding the recorders, known as "black boxes."Zelensky, however, wants the devices to be brought to Kyiv."It is very important for us," he said.