One hundred seventy-six passengers and crew died when the plane crashed shortly after taking off from Imam Khomeini International Airport in Tehran.

It took Iranian authorities three days to admit to it shot down the airliner and said it was caused by “human error.” However, until Tuesday, officials never identified anyone as being responsible for the crash.

Ukrainian officials accuse Tehran of trying to waste time, absolve its military of responsibility and skirt any settlements.

A report by Iranian investigators last month blamed an unnamed defense systems operator for firing a Tor-M1 missile that downed the Boeing 737.

Canada, which claimed 57 citizens from the death toll on Flight 752, and Ukraine have blamed Tehran for trying to downplay the crash in the report, saying investigators made “no attempt to answer critical questions about what truly happened” and offered “no hard facts or evidence.”