On August 15, 1953, U.S. and British intelligence operatives put into motion a plan to remove Iran's democratically elected Prime Minister Mohammad Mossadegh from power. The coup reached completion on August 19, when the military, backed by CIA-supported street protests, overthrew Mossadegh, installed a new prime minister, and reinstated Shah Mohammad Reza Pahlavi in the primary position of power. The events sparked massive demonstrations, leaving at least 300 people dead in gunbattles in Tehran.