Iran acknowledged on Tuesday that its armed forces fired two Russian anti-aircraft missiles at a Ukrainian jetliner that crashed after taking off from Tehran’s main airport earlier this month, killing all 176 people on board.

Iran’s top diplomat has cancelled his trip and will not be attending the Davos Forum, the Iranian Foreign Ministry said Monday amid a crisis with Washington and disputes with Europe over Iran’s nuclear steps.

The Iranian official leading the investigation into the Ukrainian jetliner that was accidentally shot down by the Revolutionary Guard appeared to backtrack Sunday on plans to send the flight recorders abroad for analysis, a day after saying they would be sent to Kyiv.

A slew of influential Iranian artists, television personalities and sports stars have publicly broken with Tehran after the government denied for days that it shot down a Ukrainian passenger plane last week, NBC News reports.

A University City woman shared the life of her cousin recently married and on his way home to Canada when his plane was shot down by Iranian officials.

Iran deployed riot police in the capital on Sunday expecting possible protests after its Revolutionary Guard admitted to accidentally shooting down a passenger plane at a time of soaring tensions with the United States.

Iran confirmed through a state-run news organization that its military unintentionally shot down the Ukrainian airplane which crashed shortly after takeoff from the Tehran airport, killing all 176 people aboard.

The U.S. and Ukraine are cooperating to find answers for the downed Ukrainian airliner that killed 167 after it crashed during takeoff from Tehran on Wednesday. The U.S. is sharing information to assist with the investigation, with Secretary of State Mike Pompeo saying the crash was “likely” caused by Iran. NBC’s Bill Neely reports from Kiev.