In which country were tens of thousands of people killed as its president to stay in power?

In Syria, tens of thousands of people have been killed during the civil war that began in 2011, largely as a result of the government's crackdown on protests against President Bashar al-Assad. The conflict escalated as Assad sought to retain power amid widespread dissent, leading to a protracted and devastating war involving multiple factions and foreign interventions. The humanitarian crisis resulting from the conflict has had far-reaching implications for the region and beyond.