In this photo provided by the Ukrainian Presidential Press Office, honor guard carry a coffin of the one of the eleven Ukrainian victims of the Boeing 737-800 plane at Borispil international airport outside Kyiv, Jan. 19, 2020.
In this photo provided by the Ukrainian Presidential Press Office, honor guard carry a coffin of the one of the eleven Ukrainian victims of the Boeing 737-800 plane at Borispil international airport outside Kyiv, Jan. 19, 2020.

The coffins of 11 Ukrainians killed when Iran's military mistakenly shot down a passenger airliner after takeoff from Tehran international airport arrived in Kyiv on Sunday as new questions emerged over Iranian officials' cooperation in ongoing investigations into the tragedy.

President Volodymyr Zelenskiy, Prime Minister Oleksiy Honcharuk, and other senior Ukrainian officials participated in a solemn ceremony after the 11 flag-draped coffins arrived in the Ukrainian capital carrying the bodies of nine Ukrainian International Airlines crew members and two passengers killed along with 165 other people when Flight PS752 went down on January 8.

Iranian officials have said that air defenses on high alert during heightened tensions after Iranian missile strikes made an error and fired antiaircraft defenses at the Boeing 737-800.

Ukrainians and officials from the four other countries that lost nationals in the disaster have demanded a "thorough, independent, and transparent" investigation.

Now, the Iranian official who is leading the investigation for Tehran has appeared to backtrack on a pledge to share the crucial black boxes that were collecting flight data aboard the aircraft.

Hassan Rezaifer, head of the accident investigations unit of Iran's civil aviation authority, was quoted on January 19 by the state-run IRNA news agency as saying "the flight recorders from the Ukrainian Boeing are in Iranian hands and we have no plans to send them out,” AP reported.

Work to read the data was ongoing, he was quoted as saying, “But as of yet, we have made no decision" on transferring the black boxes outside the country.

Rezaifer had been quoted by the Tasnim news agency as saying French, American, and Canadian experts would work with the equipment after it was sent to Kyiv because Iranian authorities had been unable to read the black-box data.

"If this effort is unsuccessful, then the black box will be sent to France," he had added, according to Tasnim.

Senior Iranian officials called for the punishment of those responsible after air-defense forces of the Islamic Revolutionary Guards Corps (IRGC) shot down the plane.

Joint Statement

The foreign ministers of Afghanistan, Britain, Canada, Sweden, and Ukraine issued a joint statement after a meeting in London on January 17 to pressure Iran to give a full accounting.

Most of the victims on the flight were Iranians or dual citizens, many of them students returning to studies abroad or families returning home after visiting relatives in Iran.

Meanwhile, Ukrainians gathered at Boryspil International Airport outside Kyiv for a ceremony on January 19 to honor the flight's casualties as their bodies arrived home for burial.

The incident came shortly after Iran launched missiles at military bases in Iraq that hosted U.S. forces, in an attack that was a response to a January 3 U.S. air strike that killed top Iranian military commander Major General Qasem Soleimani near Baghdad's international airport.

After initially denying it shot down the plane, Tehran eventually admitted that its forces "unintentionally" struck the airliner with a missile after it said it veered toward a sensitive military site.

Thousands of Iranians took to the streets to protest their government's actions, prompting public calls for punishment of the individuals responsible for the mistake.

Iranian Supreme Leader Ayatollah Ali Khamenei called for national unity and defended the country's armed forces in a rare sermon at Tehran’s Mosalla Mosque on January 17.

He accused Iran's enemies of using the plane crash to question the Islamic republic, the armed forces, and the IRGC, which he said "maintained the security" of Iran.