Thousands gathered in Tehran’s main squares Saturday afternoon to express their anger after the Iranian government admitted that its military had shot down Ukrainian International Airlines Flight 752 by mistake. The New York Times reports that gatherings that were originally planned to mourn the 176 victims of the downed plane turned into protests over the government. “Death to liars!” and “Death to the dictator!” people chanted, according to videos posted on social media reviewed by the Times. Other protesters demanded that Ayatollah Khamenei, Iran’s supreme leader, resign. “Khamenei is a murderer! His regime is obsolete!” demonstrators said. During a protest at a university, crowds called the Islamic Revolutionary Guards Corps “incompetent” and “the people’s shame.” The Times reports that some protests turned violent, with anti-riot police using tear gas and water cannons on the crowd.