Protesters piled pressure on Iran’s leadership on Sunday with demands for top authorities to quit after the Iranian military admitted it had mistakenly shot down a Ukrainian airliner at a time when it had feared U.S. strikes.

“They are lying that our enemy is America, our enemy is right here,” dozens of protesters outside a university in Tehran chanted, according to video clips posted on Twitter. Scores of demonstrators were also shown gathered in other cities.

The social media posts could not be verified by Reuters. But state-affiliated media had reported protests on Saturday shortly after the Iranian military apologized for mistakenly bringing down the Ukrainian plane on Wednesday, killing all 176 aboard.

Tehran residents told Reuters police were out in force in the capital on Sunday, as public anger boiled up following days of denials by the military that it was to blame, even as Canada and the United States said a missile had brought the plane down.

Riot police fired teargas at thousands of protesters in the capital on Saturday, where many had chanted “Death to the dictator,” directing their anger at the Islamic Republic’s Supreme Leader Ayatollah Ali Khamenei.