Ukrainian officials suggest Iran would not have admitted responsibility if investigators from Ukraine had not found missile debris in the crash wreckage. 

Protests erupted in Tehran and other Iranian cities as dumbfounded citizens found a new reason to mistrust Ayatollah Ali Khamenei, Iran’s supreme leader, and other officials. Protest videos even showed some shouting “Khamenei is a murderer!” and anti-riot police tear-gassing violent demonstrators. 

The Ukrainians further accused Iran of having recklessly permitted commercial flights during a security emergency and of having violated universally accepted procedures for a post-crash investigation. Bulldozers had heaped debris from the plane into piles on the ground. 

“Everything was done absolutely inappropriately,” Oleksiy Danilov, the Ukrainian security official overseeing the crash inquiry, said in an interview with The New York Times, referring to how Iranian authorities had handled the site of the crash.

Within Iran, as citizens vented anger toward their government, officials offered a mix of contrition and an insistence that Iran was not solely to blame. Mr. Rouhani called the error an “unforgivable mistake.” General Hajizadeh, whose forces were responsible, said he had wished death upon himself because of the blunder. 

Iran’s foreign minister, Mohammad Javad Zarif, wrote in an apology posted on twitter “Human error at time of crisis caused by US adventurism led to disaster.”